Microchip Technology 的 MIC45205-1,2 规格书

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‘ Mlcgcmp M|C45205

 2017 Microchip Technology Inc. DS20005798A-page 1

MIC45205

Features

• No Compensation Required

• Up to 6A Output Current

• >93% Peak Efficiency

• Output Voltage: 0.8V to 0.85 x VIN with ±1%

Accuracy

• Adjustable Switching Frequency from 200 kHz to

600 kHz

• Enable Input and Open-Drain Power Good Output

• HyperLight Load (MIC45205-1) Improves Light

Load Efficiency

• Hyper Speed Control (MIC45205-2) Architecture

Enables Fast Transient Response

• Supports Safe Startup into Pre-Biased Output

• –40°C to +125°C Junction Temperature Range

• Thermal Shutdown Protection

• Short-Circuit Protection with Hiccup Mode

• Adjustable Current-Limit

• Available in 52-pin 8 mm × 8 mm × 3 mm QFN

Package

Applications

• High Power Density Point-of-Load Conversion

• Servers, Routers, Networking, and Base Stations

• FPGAs, DSP, and Low-Voltage ASIC Power

Supplies

• Industrial and Medical Equipment

General Description

MIC45205 is a synchronous step-down regulator

module, featuring a unique adaptive ON-time control

architecture. The module incorporates a DC/DC

controller, power MOSFETs, bootstrap diode, bootstrap

capacitor, and an inductor in a single package;

simplifying the design and layout process for the end

user.

This highly integrated solution expedites system

design and improves product time-to-market. The

internal MOSFETs and inductor are optimized to

achieve high efficiency at a low output voltage. The fully

optimized design can deliver up to 6A current under a

wide input voltage range of 4.5V to 26V, without

requiring additional cooling.

The MIC45205-1 uses Microchip’s HyperLight Load®

(HLL) and the MIC45205-2 uses Microchip’s Hyper

Speed Control® architecture that enables ultra-fast

load transient response, allowing for a reduction of

output capacitance. The MIC45205 offers 1% output

accuracy that can be adjusted from 0.8V to 0.85 x VIN

with two external resistors. Additional features include

thermal shutdown protection, input undervoltage

lockout, adjustable current-limit, and short-circuit

protection. The MIC45205 allows for safe start-up into

a pre-biased output.

Typical Application Diagram

RFB1

VOUT

UP to 6A

MIC45205

VIN

12V

COUT

CIN

GND

PVIN VOUT

RFB2

ILIM

PGND

BST

ANODE

FREQ

PVDD

5VDD

RLIM

RIB

OFF

VIN CFF

RIA

26V/6A DC/DC Power Module

MIC45205

DS20005798A-page 2  2017 Microchip Technology Inc.

Functional Block Diagram

PWM

CONTROLLER

VOUT

PVIN

BST

ILIM

PVDD

PGND

5VDD

FREQ

GND

VIN BST

ANODE

PGND

VDD

AGND

PVDD

ILIM

FREQ

VIN

RIA

INJ

RIB

SVDD SVDD 'FB BIAS ENHIGH

 2017 Microchip Technology Inc. DS20005798A-page 3

MIC45205

1.0 ELECTRICAL CHARACTERISTICS

Absolute Maximum Ratings †

VPVIN, VVIN to PGND ................................................................................................................................. –0.3V to +30V

VPVDD, V5VDD, VANODE to PGND................................................................................................................. –0.3V to +6V

VSW, VFREQ, VILIM, VEN to PGND ....................................................................................................–0.3V to (VIN + 0.3V)

VBST to VSW ................................................................................................................................................. –0.3V to +6V

VBST to PGND............................................................................................................................................ –0.3V to +36V

VPG to PGND ............................................................................................................................... –0.3V to (5VDD + 0.3V)

VFB, VRIB to PGND ...................................................................................................................... –0.3V to (5VDD + 0.3V)

PGND to GND........................................................................................................................................... –0.3V to +0.3V

Operating Ratings ‡

Supply Voltage (VPVIN, VVIN) ..................................................................................................................... +4.5V to +26V

Output Current ..............................................................................................................................................................6A

Enable Input (VEN) ..............................................................................................................................................0V to VIN

Power Good (VPG) .......................................................................................................................................... 0V to 5VDD

† Notice: Stresses above those listed under “Absolute Maximum Ratings” may cause permanent damage to the device.

This is a stress rating only and functional operation of the device at those or any other conditions above those indicated

in the operational sections of this specification is not intended. Exposure to maximum rating conditions for extended

periods may affect device reliability.

‡ Notice: The device is not guaranteed to function outside its operating ratings.

TABLE 1-1: ELECTRICAL CHARACTERISTICS

Electrical Characteristics: VIN = VEN = 12V, VOUT = 3.3V, VBST – VSW = 5V, TJ = +25ºC. Bold values indicate

–40ºC < TJ < +125ºC, unless otherwise noted. Note 1

Parameter Symbol Min. Typ. Max. Units Conditions

Power Supply Input

Input Voltage Range VIN, PVIN 4.5 —26 V—

Quiescent Supply Current

(MIC45205-1) IQ—0.350.75 mA VFB = 1.5V

Quiescent Supply Current

(MIC45205-2) IQ—2.1 3mA VFB = 1.5V

Operating Current IIN —31— mA

VPVIN = VIN = 12V, VOUT = 1.8V,

IOUT = 0A

fSW = 600 kHz (MIC45205-2)

Shutdown Supply Current ISHDN —0.110 µA SW = unconnected, VEN = 0V

5VDD Output

5VDD Output Voltage VDD 4.8 5.1 5.4 VV

IN = 7V to 26V, I5VDD = 10 mA

5VDD UVLO Threshold UVLO 3.8 4.2 4.6 VV

5VDD rising

5VDD UVLO Hysteresis UVLO_

HYS —400— mVV

5VDD falling

LDO Load Regulation VDD(LR) 0.6 2 3.6 % I5VDD = 0 mA to 40 mA

Reference

Feedback Reference Voltage VFB

0.792 0.8 0.808 VTJ = +25°C

0.784 0.8 0.816 –40°C  TJ  +125°C

FB Bias Current IFB_BIAS —5500 nA VFB = 0.8V

Enable Control

EN Logic Level High ENHIGH 1.8 —— V—

ENB‘AS DMAX ‘OFF MW LEAKAGE LEAK

MIC45205

DS20005798A-page 4  2017 Microchip Technology Inc.

EN Logic Level Low ENLOW ——0.6 V—

EN Hysteresis ENHYS —200— mV—

EN Bias Current IENBIAS —510 µA VEN = 12V

Oscillator

Switching Frequency fSW

400 600 750 kHz VFREQ = VIN, IOUT = 2A

—350— V

FREQ = 50% VIN, IOUT = 2A

Maximum Duty Cycle DMAX —85— %—

Minimum Duty Cycle DMIN —0— %V

FB = 1V

Minimum Off-Time tOFF(MIN) 140 200 260 ns —

Soft-Start

Soft-Start Time tSS — 5 — ms FB from 0V to 0.8V

Short-Circuit Protection

Current-Limit Threshold VCL_

OFFSET

–30 –14 0 mV VFB = 0.79V

Short-Circuit Threshold VSC –23 –7 9 mV VFB = 0V

Current-Limit Source Current ICL 55 70 85 µA VFB = 0.79V

Short-Circuit Source Current ISC 25 35 45 µA VFB = 0V

Leakage

SW, BST Leakage Current ISW_

LEAKAGE

— — 10 µA —

FREQ Leakage Current IFREQ_

LEAK

— — 10 µA —

Power Good (PG)

PG Threshold Voltage VPG_TH 85 90 95 % VOUT Sweep VFB from Low-to-High

PG Hysteresis VPG_HYS —6—% V

OUT Sweep VFB from High-to-Low

PG Delay Time tPG_DLY — 100 — µs Sweep VFB from Low-to-High

PG Low Voltage VPG_LOW —70200 mV VFB < 90% × VNOM, IPG = 1 mA

Thermal Protection

Overtemperature Shutdown TSHD —160— °CT

J rising

Overtemperature Shutdown

Hysteresis

TSHD_

HYS

—15— °C—

Note 1: Specification for packaged product only.

TABLE 1-1: ELECTRICAL CHARACTERISTICS (CONTINUED)

Electrical Characteristics: VIN = VEN = 12V, VOUT = 3.3V, VBST – VSW = 5V, TJ = +25ºC. Bold values indicate

–40ºC < TJ < +125ºC, unless otherwise noted. Note 1

Parameter Symbol Min. Typ. Max. Units Conditions

 2017 Microchip Technology Inc. DS20005798A-page 5

MIC45205

TEMPERATURE SPECIFICATIONS (Note 1)

Parameters Sym. Min. Typ. Max. Units Conditions

Temperature Ranges

Junction Operating Temperature

Range

TJ–40 — +125 °C —

Maximum Junction Temperature — — — +150 °C —

Storage Temperature Range TS–65 — +150 °C —

Lead Temperature — — — +260 °C Soldering, 10s

Package Thermal Resistances

Thermal Resistance QFN-52 JA —21.7 —°C/WNote 2

Thermal Resistance QFN-52 JC —5.0 —°C/WNote 2

Note 1: The maximum allowable power dissipation is a function of ambient temperature, the maximum allowable

junction temperature and the thermal resistance from junction to air (i.e., TA, TJ, JA). Exceeding the

maximum allowable power dissipation will cause the device operating junction temperature to exceed the

maximum +125°C rating. Sustained junction temperatures above +125°C can impact the device reliability.

2: JA and JC were measured using the MIC45205 evaluation board.

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MIC45205

DS20005798A-page 6  2017 Microchip Technology Inc.

2.0 TYPICAL PERFORMANCE CURVES

FIGURE 2-1: VIN Operating Supply

Current vs. Temperature (MIC45205-1).

FIGURE 2-2: VDD Supply Voltage vs.

Temperature.

FIGURE 2-3: Enable Threshold vs.

Temperature.

FIGURE 2-4: EN Bias Current vs.

Temperature.

FIGURE 2-5: Feedback Voltage vs.

Temperature.

FIGURE 2-6: Output Voltage vs.

Temperature.

Note: The graphs and tables provided following this note are a statistical summary based on a limited number of

samples and are provided for informational purposes only. The performance characteristics listed herein

are not tested or guaranteed. In some graphs or tables, the data presented may be outside the specified

operating range (e.g., outside specified power supply range) and therefore outside the warranted range.

SWI‘ICHING FREQUENCY (kHz) sun am mo sun 5m 4m) we 5a 725 u 25 in 15 «an 125 TEMPERATURE (“0) EFFICIENCY 0/.) 1 2 3 4 5 5 7 a n UuTFUTcURRENT(AI CHRRENY LIMW (A) 25 q 25 5a 75 um :25 TEMPERATURE ['c) EFFlclEucvl‘r-l um ﬂu an m an an m an Zn in kw - mm; 1 2 3 4 5 5 7 a s OUTPUT CURRENT (A! EFFICIENCVI‘f-l mu an En Tu an Su M 30 500ka 20 m nIzaAssvag OUTPUT CURRENT (m 1L IZSJSBTEB DUTPUY CURRENT (A)

 2017 Microchip Technology Inc. DS20005798A-page 7

MIC45205

FIGURE 2-7: Switching Frequency vs.

Temperature.

FIGURE 2-8: Output Peak Current Limit

vs. Temperature.

FIGURE 2-9: Efficiency (VIN = 5V) vs.

Output Current (MIC45205-1).

FIGURE 2-10: Efficiency (VIN = 12V) vs.

Output Current (MIC45205-1).

FIGURE 2-11: Efficiency (VIN = 24V) vs.

Output Current (MIC45205-1).

FIGURE 2-12: Efficiency (VIN = 5V) vs.

Output Current (MIC45205-2).

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MIC45205

DS20005798A-page 8  2017 Microchip Technology Inc.

FIGURE 2-13: Efficiency (VIN = 12V) vs.

Output Current (MIC45205-2).

FIGURE 2-14: Efficiency (VIN = 24V) vs.

Output Current (MIC45205-2).

FIGURE 2-15: Line Regulation.

FIGURE 2-16: Output Voltage vs. Input

Voltage.

FIGURE 2-17: IC Power Dissipation (VIN =

5V) vs. Output Current.

FIGURE 2-18: IC Power Dissipation (VIN =

12V) vs. Output Current.

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 2017 Microchip Technology Inc. DS20005798A-page 9

MIC45205

FIGURE 2-19: IC Power Dissipation (VIN =

24V) vs. Output Current.

FIGURE 2-20: VIN Soft Turn-On.

FIGURE 2-21: VIN Soft Turn-Off.

FIGURE 2-22: Enable Turn-On Delay and

Rise Time.

FIGURE 2-23: Enable Turn-Off Delay and

Fall Time.

FIGURE 2-24: VIN Start-Up with

Pre-Biased Output.

Time (2ms/div)

IIN

(2A/div)

VIN

(10V/div)

VOUT

(1V/div)

PGOOD

(5V/div)

VIN = 12V

VOUT = 1.8V

IOUT = 6A

Time (2ms/div)

IIN

(2A/div)

VIN

(10V/div)

VOUT

(1V/div)

PGOOD

(5V/div)

VIN = 12V

VOUT = 1.8V

IOUT = 6A

Time (2ms/div)

VEN

(2V/div)

VOUT

(1V/div)

IIN

(1A/div)

VIN = 12V

VOUT = 1.8V

IOUT = 6A

Time (2ms/div)

VEN

(2V/div)

VOUT

(1V/div)

IIN

(1A/div)

VIN = 12V

VOUT = 1.8V

IOUT = 6A

Time (2ms/div)

VIN

(10V/div)

VOUT

(1V/div)

PGOOD

(5V/div) VIN = 12V

VOUT = 1.8V

IOUT = 1A

VPRE-BIAS = 0.5V

I///////////// W_L/////////////

MIC45205

DS20005798A-page 10  2017 Microchip Technology Inc.

FIGURE 2-25: Enable Turn-On/Off.

FIGURE 2-26: Power-Up Into Short-Circuit.

FIGURE 2-27: Enabled Into Short-Circuit.

FIGURE 2-28: Short-Circuit.

FIGURE 2-29: Output Recovery from

Short-Circuit.

FIGURE 2-30: Peak Current-Limit

Threshold.

Time (8ms/div)

VEN

(2V/div)

VOUT

(1V/div)

IIN

(1A/div)

VIN = 12V

VOUT = 1.8V

IOUT = 6A

Time (2ms/div)

VIN

(10V/div)

VOUT

(20mV/div)

IIN

(500mA/div)

VIN = 12V, VOUT = 1.8V

IOUT = SHORT CIRCUIT

Time (400μs/div)

VEN

(2V/div)

VOUT

(20mV/div)

VIN = 12V

VOUT = 1.8V

IOUT = SHORT CIRCUIT

IIN

(100mA/div)

Time (2ms/div)

VOUT

(1V/div)

IOUT

(5A/div)

VIN = 12V

VOUT = 1.8V

Time (8ms/div)

VOUT

(1V/div)

IOUT

(5A/div)

VIN = 12V

VOUT = 1.8V

Time (4ms/div)

VOUT

(1V/div)

IOUT

(5A/div)

VIN = 12V

VOUT = 1.8V

IPK_CL = 8.4A

 2017 Microchip Technology Inc. DS20005798A-page 11

MIC45205

FIGURE 2-31: Output Recovery from

Thermal Shutdown.

FIGURE 2-32: Switching Waveforms (IOUT

= 6A).

FIGURE 2-33: Switching Waveforms,

MIC45205-1 (IOUT = 0A).

FIGURE 2-34: Inrush with COUT = 3000 µF.

FIGURE 2-35: Transient Response,

MIC45205-1 (IOUT = 3A to 6A).

FIGURE 2-36: Transient Response,

MIC45205-1 (IOUT = 0.5A to 3.5A).

Time (2ms/div)

VOUT

(1V/div)

(5V/div)

VSW

(5V/div)

VIN = 12V

VOUT = 1.8V

IOUT = 6A

Time (1μs/div)

VOUT

(AC-COUPLED)

(20mV/div)

IOUT

(5A/div)

VSW

(5V/div)

VIN = 12V

VOUT = 1.8V

IOUT = 6A

Time (20ms/div)

VOUT

(AC-COUPLED)

(20mV/div)

IOUT

(2A/div)

VSW

(5V/div) VIN = 12V

VOUT = 1.8V

IOUT = 0A

Time (8ms/div)

VEN

(2V/div)

IIN

(1A/div)

VIN = 12V

VOUT = 1.8V

IOUT = 6A

VOUT

(1V/div)

Time (100μs/div)

VOUT

(100mV/div)

IOUT

(2A/div)

VIN = 12V

VOUT = 1.8V

IOUT = 3A TO 6A

Time (100μs/div)

VOUT

(100mV/div)

IOUT

(2A/div)

VIN = 12V

VOUT = 1.8V

IOUT = 0.5A TO 3.5A

PVDD DD

MIC45205

DS20005798A-page 12  2017 Microchip Technology Inc.

3.0 PIN DESCRIPTIONS

FIGURE 3-1: MIC45205 Pin Configuration.

The descriptions of the pins are listed in Table 3-1.

TABLE 3-1: PIN FUNCTION TABLE

Pin Number Pin Name Description

1GND

Analog Ground. Connect bottom feedback resistor to GND. GND and PGND are

internally connected.

2, 3 5VDD

Internal +5V Linear Regulator Output. Powered by VIN, 5VDD is the internal supply

bus for the device. In the applications with VIN < +5.5V, 5VDD should be tied to VIN to

bypass the linear regulator.

4, 5 PVDD PVDD. Supply input for the internal low-side power MOSFET driver.

6, 7, 8, 45, 52 PGND

Power Ground. PGND is the return path for the step-down power module power

stage. The PGND pin connects to the sources of internal low-side power MOSFET,

the negative terminals of input capacitors, and the negative terminals of output

capacitors.

10, 11, 12, 31,

32, 33, 34 SW

The SW pin connects directly to the switch node. Due to the high-speed switching on

this pin, the SW pin should be routed away from sensitive nodes. The SW pin also

senses the current by monitoring the voltage across the low-side MOSFET during

OFF time.

14, 15, 16, 17,

18, 19 PVIN

Power Input Voltage. Connection to the drain of the internal high-side power

MOSFET. Connect an input capacitor from PVIN to PGND.

21, 22, 23, 24,

25, 26, 27, 28,

VOUT

Output Voltage. Connected to the internal inductor, the output capacitor should be

connected from this pin to PGND as close to the module as possible.

36, 37, 38 RIA Ripple Injection Pin A. Leave floating, no connection.

GND

5VDD

KEEPOUT

PVDD

PGND

KEEPOUT

PVIN

ANODE

RIB

VOUT

RIA

KEEPOUT

VOUT

PGND

ILIM

FREQ

VIN

PGND

BST

PVIN

KEEPOUT

VOUT

PGND

PVIN ePAD VOUT ePAD

 2017 Microchip Technology Inc. DS20005798A-page 13

MIC45205

39 RIB Ripple Injection Pin B. Connect this pin to FB.

40, 41 ANODE Anode Bootstrap Diode. Anode connection of internal bootstrap diode, this pin should

be connected to the PVDD pin.

42, 43, 44 BST Connection to the internal bootstrap circuitry and high-side power MOSFET drive

circuitry. Connect all three BST pins together.

46 FB

Feedback. Input to the transconductance amplifier of the control loop. The FB pin is

referenced to 0.8V. A resistor divider connecting the feedback to the output is used to

set the desired output voltage. Connect the bottom resistor from FB to GND.

47 PG Power Good. Open-drain output. If used, connect to an external pull-up resistor of at

least 10 k between PG and the external bias voltage.

48 EN

Enable. A logic signal to enable or disable the step-down regulator module operation.

The EN pin is TTL/CMOS compatible. Logic-high = enable, logic-low = disable or

shutdown. EN pin has an internal 1 M (typical) pull-down resistor to GND. Do not

leave floating.

49 VIN

Internal 5V Linear Regulator Input. A 1 F ceramic capacitor from VIN to GND is

required for decoupling.

50 FREQ Switching Frequency Adjust. Use a resistor divider from VIN to GND to program the

switching frequency. Connecting FREQ to VIN sets frequency at 600 kHz.

51 ILIM Current Limit. Connect a resistor between ILIM and SW to program the current limit.

9, 13, 20, 30, 35 KEEPOUT Depopulated pin positions.

—PV

IN ePAD PVIN Exposed Pad. Internally connected to PVIN pins. Please see PCB Layout

Guidelines section.

—VOUT

ePAD

VOUT Exposed Pad. Internally connected to VOUT pins. Please see PCB Layout

Guidelines section.

TABLE 3-1: PIN FUNCTION TABLE (CONTINUED)

Pin Number Pin Name Description

MIC45205

DS20005798A-page 14  2017 Microchip Technology Inc.

4.0 FUNCTIONAL DESCRIPTION

The MIC45205 is an adaptive on-time synchronous

buck regulator module built for high-input voltage to

low-output voltage conversion applications. The

MIC45205 is designed to operate over a wide input

voltage range, from 4.5V to 26V, and the output is

adjustable with an external resistor divider. An adaptive

on-time control scheme is employed to obtain a

constant switching frequency in steady state and to

simplify the control compensation. Hiccup mode

overcurrent protection is implemented by sensing

low-side MOSFET’s RDS(ON). The device features

internal soft-start, enable, UVLO, and thermal

shutdown. The module has integrated switching FETs,

inductor, bootstrap diode, resistor, and capacitor.

4.1 Theory of Operation

As shown in Figure 4-1 (in association with

Equation 4-1), the output voltage is sensed by the

MIC45205 feedback pin (FB) via the voltage divider

RFB1 and RFB2 and compared to a 0.8V reference

voltage (VREF) at the error comparator through a

low-gain transconductance (gm) amplifier. If the

feedback voltage decreases, and the amplifier output

falls below 0.8V, then the error comparator will trigger

the control logic and generate an ON-time period. The

ON-time period length is predetermined by the “Fixed

tON Estimator” circuitry:

FIGURE 4-1: Output Voltage Sense via

FB Pin.

EQUATION 4-1:

At the end of the ON-time period, the internal high-side

driver turns off the high-side MOSFET and the low-side

driver turns on the low-side MOSFET. The OFF-time

period length depends upon the feedback voltage in

most cases. When the feedback voltage decreases

and the output of the gm amplifier falls below 0.8V, the

ON-time period is triggered and the OFF-time period

ends. If the OFF-time period determined by the

feedback voltage is less than the minimum OFF-time

tOFF(MIN), which is about 200 ns, the MIC45205 control

logic will apply the tOFF(MIN) instead. tOFF(MIN) is

required to maintain enough energy in the boost

capacitor (CBST) to drive the high-side MOSFET.

The maximum duty cycle is obtained from the 200 ns

tOFF(MIN):

EQUATION 4-2:

It is not recommended to use MIC45205 with an

OFF-time close to tOFF(MIN) during steady-state

operation.

The adaptive ON-time control scheme results in a

constant switching frequency in the MIC45205 during

steady state operation. The actual ON-time and

resulting switching frequency will vary with the different

rising and falling times of the MOSFETs. Also, the

minimum tON results in a lower switching frequency in

high VIN to VOUT applications. During load transients,

the switching frequency is changed due to the varying

OFF-time.

To illustrate the control loop operation, we will analyze

both the steady-state and load transient scenarios. For

easy analysis, the gain of the gm amplifier is assumed

to be 1. With this assumption, the inverting input of the

error comparator is the same as the feedback voltage.

Figure 4-2 shows the MIC45205 control loop timing

during steady-state operation. During steady-state, the

gm amplifier senses the feedback voltage ripple, which

is proportional to the output voltage ripple plus injected

voltage ripple, to trigger the ON-time period. The

ON-time is predetermined by the tON estimator. The

termination of the OFF-time is controlled by the

feedback voltage. At the valley of the feedback voltage

ripple, which occurs when VFB falls below VREF

, the

OFF period ends and the next ON-time period is

triggered through the control logic circuitry.

COMPENSATION

COMP

RFB1

RFB2

VREF

0.8V

VOUT

gM EA

tON ESTIMATED

VOUT

VIN fSW



-----------------------=

Where:

VOUT Output Voltage

VIN Power Stage Input Voltage

fSW Switching Frequency

DMAX

tStOFF MIN

–

-----------------------------------1

200ns

---------------–==

Where:

tS1/fSW

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 2017 Microchip Technology Inc. DS20005798A-page 15

MIC45205

FIGURE 4-2: MIC45205 Control Loop

Timing.

Figure 4-3 shows the operation of the MIC45205 during

a load transient. The output voltage drops due to the

sudden load increase, which causes the VFB to be less

than VREF

. This will cause the error comparator to

trigger an ON-time period. At the end of the ON-time

period, a minimum OFF-time tOFF(MIN) is generated to

charge the bootstrap capacitor (CBST) because the

feedback voltage is still below VREF

. Then, the next

ON-time period is triggered due to the low feedback

voltage. Therefore, the switching frequency changes

during the load transient, but returns to the nominal

fixed frequency once the output has stabilized at the

new load current level. With the varying duty cycle and

switching frequency, the output recovery time is fast

and the output voltage deviation is small. Note that the

instantaneous switching frequency during load

transient remains bounded and cannot increase

arbitrarily. The minimum is limited by tON + tOFF(MIN).

Because the variation in VOUT is relatively limited

during load transient, tON stays virtually close to its

steady-state value.

FIGURE 4-3: MIC45205 Load Transient

Response.

Unlike true current-mode control, the MIC45205 uses

the output voltage ripple to trigger an ON-time period.

The output voltage ripple is proportional to the inductor

current ripple if the ESR of the output capacitor is large

enough.

In order to meet the stability requirements, the

MIC45205 feedback voltage ripple should be in phase

with the inductor current ripple and are large enough to

be sensed by the gm amplifier and the error

comparator. The recommended feedback voltage

ripple is 20 mV~100 mV over full input voltage range. If

a low ESR output capacitor is selected, then the

feedback voltage ripple may be too small to be sensed

by the gm amplifier and the error comparator. Also, the

output voltage ripple and the feedback voltage ripple

are not necessarily in phase with the inductor current

ripple if the ESR of the output capacitor is very low. In

these cases, ripple injection is required to ensure

proper operation. Please refer to the Ripple Injection

subsection in the Application Information section for

more details about the ripple injection technique.

4.2 Discontinuous Mode (MIC45205-1

Only)

In continuous mode, the inductor current is always

greater than zero. However, at light loads, the

MIC45205-1 is able to force the inductor current to

operate in discontinuous mode. Discontinuous mode is

where the inductor current falls to zero, as indicated by

trace (IL) shown in Figure 4-4. During this period, the

efficiency is optimized by shutting down all the

non-essential circuits and minimizing the supply

current as the switching frequency is reduced. The

MIC45205-1 wakes up and turns on the high-side

MOSFET when the feedback voltage VFB drops below

0.8V.

The MIC45205-1 has a zero crossing comparator (ZC)

that monitors the inductor current by sensing the

voltage drop across the low-side MOSFET during its

ON-time. If the VFB > 0.8V and the inductor current

goes slightly negative, then the MIC45205-1

automatically powers down most of the IC circuitry and

goes into a low-power mode.

Once the MIC45205-1 goes into discontinuous mode,

both DL and DH are low, which turns off the high-side

and low-side MOSFETs. The load current is supplied

by the output capacitors and VOUT drops. If the drop of

VOUT causes VFB to go below VREF

, then all the circuits

will wake up into normal continuous mode. First, the

bias currents of most circuits reduced during the

discontinuous mode are restored, and then a tON pulse

is triggered before the drivers are turned on to avoid

any possible glitches. Finally, the high-side driver is

turned on. Figure 4-4 shows the control loop timing in

discontinuous mode.

RFB2

RFB1 + RFB2

VREF

\ CROSSES mum v“ > a a mscoNnNuous MODE STARTS v a5 WAKEVUPFROM l‘ D‘SCOMTINUOUS MCDE m 1 ESWMED own/1r. ‘IF—IW .7 .

MIC45205

DS20005798A-page 16  2017 Microchip Technology Inc.

FIGURE 4-4: MIC45205-1 Control Loop

Timing (Discontinuous Mode).

During discontinuous mode, the bias current of most

circuits is substantially reduced. As a result, the total

power supply current during discontinuous mode is

only about 350 µA, allowing the MIC45205-1 to

achieve high efficiency in light load applications.

4.3 Soft-Start

Soft-start reduces the input power supply surge current

at startup by controlling the output voltage rise time.

The input surge appears while the output capacitor is

charged up.

The MIC45205 implements an internal digital soft-start

by making the 0.8V reference voltage VREF ramp from

0 to 100% in about 5 ms with 9.7 mV steps. Therefore,

the output voltage is controlled to increase slowly by a

stair-case VFB ramp. Once the soft-start cycle ends, the

related circuitry is disabled to reduce current

consumption. PVDD must be powered up at the same

time or after VIN to make the soft-start function

correctly.

4.4 Current-Limit

The MIC45205 uses the RDS(ON) of the low-side

MOSFET and external resistor connected from ILIM pin

to SW node to set the current limit.

FIGURE 4-5: MIC45205 Current-Limiting

Circuit.

In each switching cycle of the MIC45205, the inductor

current is sensed by monitoring the low-side MOSFET

in the OFF period. The sensed voltage VILIM is

compared with the power ground (PGND) after a

blanking time of 150 ns. In this way the drop voltage

over the resistor R15 (VCL) is compared with the drop

over the bottom FET generating the short current limit.

The small capacitor (C15) connected from ILIM pin to

PGND filters the switching node ringing during the

off-time allowing a better short-limit measurement. The

time constant created by R15 and C15 should be much

less than the minimum off time.

The VCL drop allows programming of short limit through

the value of the resistor (R15). If the absolute value of

the voltage drop on the bottom FET becomes greater

than VCL, and the VILIM falls below PGND, an

overcurrent is triggered causing the IC to enter hiccup

mode. The hiccup sequence including the soft-start

reduces the stress on the switching FETs and protects

the load and supply for severe short conditions.

The short-circuit current-limit can be programmed by

using Equation 4-3.

EQUATION 4-3:

VIN

MIC45205

BST

PGND

ILIM

R15

C15

R15 ICLIM ILPP

–0.5RDS ON

VCL_OFFSET

+

ICL

------------------------------------------------------------------------------------------------------------------------=

Where:

ICLIM Desired current limit.

RDS(ON) On-resistance of low-side power

MOSFET, 16 m typically.

VCL_

OFFSET

Current-limit threshold (typ. 14 mV).

ICL Current-limit source current (typ.

70 µA).

IL(PP) Inductor current peak-to-peak.

 2017 Microchip Technology Inc. DS20005798A-page 17

MIC45205

Because the inductor is integrated, use Equation 4-4 to

calculate the inductor ripple current.

EQUATION 4-4:

The MIC45205 has a 1.0 µH inductor integrated into

the module. In case of a hard short, the short limit is

folded down to allow an indefinite hard short on the

output without any destructive effect. It is mandatory to

make sure that the inductor current used to charge the

output capacitance during soft-start is under the folded

short limit; otherwise the supply will go in hiccup mode

and may not finish the soft-start successfully.

The MOSFET RDS(ON) varies 30% to 40% with

temperature; therefore, it is recommended to add a

50% margin to ICLIM in Equation 4-3 to avoid false

current limiting due to increased MOSFET junction

temperature rise.

With R15 = 1.37 k and C15 = 15 pF, the typical output

current-limit is 8A.

ILPP

VOUT VIN MAX

VOUT

–

VIN MAX

fSW

L

--------------------------------------------------------------------=

MIC45205

DS20005798A-page 18  2017 Microchip Technology Inc.

5.0 APPLICATION INFORMATION

5.1 Setting the Switching Frequency

The MIC45205 switching frequency can be adjusted by

changing the value of resistors R1 and R2.

FIGURE 5-1: Switching Frequency

Adjustment.

Equation 5-1 gives the estimated switching frequency:

EQUATION 5-1:

FIGURE 5-2: Switching Frequency vs. R2.

5.2 Output Capacitor Selection

The type of the output capacitor is usually determined

by the application and its equivalent series resistance

(ESR). Voltage and RMS current capability are two

other important factors for selecting the output

capacitor. Recommended capacitor types are MLCC,

OS-CON and POSCAP. The output capacitor’s ESR is

usually the main cause of the output ripple. The

MIC45205 requires ripple injection and the output

capacitor ESR affects the control loop from a stability

point of view.

The maximum value of ESR is calculated as in

Equation 5-2:

EQUATION 5-2:

The total output ripple is a combination of the ESR and

output capacitance. The total ripple is calculated in

Equation 5-3:

EQUATION 5-3:

As described in the Theory of Operation subsection in

the Functional Description, the MIC45205 requires at

least 20 mV peak-to-peak ripple at the FB pin to make

the gm amplifier and the error comparator behave

properly. Also, the output voltage ripple should be in

phase with the inductor current. Therefore, the output

voltage ripple caused by the output capacitors value

should be much smaller than the ripple caused by the

output capacitor ESR. If low-ESR capacitors, such as

ceramic capacitors, are selected as the output

capacitors, a ripple injection method should be applied

to provide enough feedback voltage ripple. Please refer

to the Ripple Injection subsection in the Application

Information section for more details.

VIN

MIC45205

BST

PGND

FREQ

fSW fOR2

R1R2+

--------------------

=

Where:

fO600 kHz (typical per the Electrical

Characteristics table).

R1 100 k is recommended.

R2 Needs to be selected in order to set the

required switching frequency.

100

200

300

400

500

600

700

800

10.00 100.00 1000.00 10000.00

SW FREQ (kHz)

R2 (kȍ)

OUT

= 5V

= 12V

R1 = 100kȍ

ESRCOUT

VOUT PP



ILPP



---------------------------



Where:

VOUT(PP) Peak-to-peak output voltage ripple

IL(PP) Peak-to-peak inductor current

ripple

VOUT PP



ILPP



COUT fSW

8

--------------------------------------





2ILPP

ESRCOUT



Where:

COUT Output Capacitance Value

fSW Switching Frequency

Alum» JDMh) WW

 2017 Microchip Technology Inc. DS20005798A-page 19

MIC45205

The output capacitor RMS current is calculated in

Equation 5-4:

EQUATION 5-4:

The power dissipated in the output capacitor is:

EQUATION 5-5:

5.3 Input Capacitor Selection

The input capacitor for the power stage input PVIN

should be selected for ripple current rating and voltage

rating. The input voltage ripple will primarily depend on

the input capacitor’s ESR. The peak input current is

equal to the peak inductor current, so:

EQUATION 5-6:

The input capacitor must be rated for the input current

ripple. The RMS value of input capacitor current is

determined at the maximum output current. Assuming

the peak-to-peak inductor current ripple is low:

EQUATION 5-7:

The power dissipated in the input capacitor is:

EQUATION 5-8:

The general rule is to pick the capacitor with a ripple

current rating equal to or greater than the calculated

worst-case RMS capacitor current.

Equation 5-9 should be used to calculate the input

capacitor. Also it is recommended to keep some margin

on the calculated value:

EQUATION 5-9:

5.4 Output Voltage Setting

Components

The MIC45205 requires two resistors to set the output

voltage as shown in Figure 5-3:

FIGURE 5-3: Voltage-Divider

Configuration.

The output voltage is determined by Equation 5-10:

ICOUT RMS

ILPP



------------------=

PDISS COUT

ICOUT RMS

2ESRCOUT

=

VIN

ILPK

ESRCIN

=

ICIN RMS

IOUT MAXD1D–

Where:

D Duty cycle

PDISS CINICIN RMS

2ESRCIN

=

CIN

IOUT MAX

1D–

fSW dV

---------------------------------------------------



Where:

dV Input ripple

fSW Switching frequency

RFB1

RFB2

VREF

gM AMP

MIC45205

DS20005798A-page 20  2017 Microchip Technology Inc.

EQUATION 5-10:

A typical value of RFB1 used on the standard evaluation

board is 10 k. If R1 is too large, it may allow noise to

be introduced into the voltage feedback loop. If RFB1 is

too small in value, it will decrease the efficiency of the

power supply, especially at light loads. Once RFB1 is

selected, RFB2 can be calculated using Equation 5-11:

EQUATION 5-11:

For fixed RFB1 = 10 k, output voltage can be selected

by RFB2. Ta b l e 5 - 1 provides RFB2 values for some

common output voltages.

5.5 Ripple Injection

The VFB ripple required for proper operation of the

MIC45205 gm amplifier and error comparator is 20 mV

to 100 mV. However, the output voltage ripple is

generally too small to provide enough ripple amplitude

at the FB pin and this issue is more visible in lower

output voltage applications. If the feedback voltage

ripple is so small that the gm amplifier and error

comparator cannot sense it, then the MIC45205 will

lose control and the output voltage is not regulated. In

order to have some amount of VFB ripple, a ripple

injection method is applied for low output voltage ripple

applications.

The applications are divided into two situations

according to the amount of the feedback voltage ripple:

1. Enough ripple at the feedback voltage due to the

large ESR of the output capacitors:

As shown in Figure 5-4, the converter is stable without

any ripple injection.

FIGURE 5-4: Enough Ripple at FB from

ESR.

The feedback voltage ripple is:

EQUATION 5-12:

2. Virtually no or inadequate ripple at the FB pin

voltage due to the very-low ESR of the output

capacitors, such is the case with ceramic output

capacitor. In this case, the VFB ripple waveform

needs to be generated by injecting suitable sig-

nal. MIC45205 has provisions to enable an inter-

nal series RC injection network, RINJ and CINJ

as shown in Figure 5-5 by connecting RIB to the

FB pin. This network injects a square-wave cur-

rent waveform into the FB pin, which, by means

of integration across the capacitor (C14), gener-

ates an appropriate sawtooth FB ripple wave-

form.

FIGURE 5-5: Internal Ripple Injection at

FB via RIB Pin.

TABLE 5-1: VOUT PROGRAMMING

RESISTOR LOOK-UP

RFB2 VOUT

OPEN 0.8V

40.2 k1.0V

20 k1.2V

11.5 k1.5V

8.06 k1.8V

4.75 k2.5V

3.24 k3.3V

1.91 k5.0V

VOUT VFB 1RFB1

RFB2

------------+





=

Where:

VFB 0.8V

RFB2

VFB RFB1



VOUT VFB

–

-----------------------------=

RFB1

RFB2

ESR

COUT

VOUT

MIC45205

VFB PP

RFB2

RFB1RFB2

------------------------------- ESRCOUT

ILPP

=

Where:

IL(PP) The peak-to-peak value of the inductor

current ripple

RFB1

RFB2

ESR

COUT

VOUT

MIC45205

C14

RIB

RIA

RINJ

CINJ

N W

 2017 Microchip Technology Inc. DS20005798A-page 21

MIC45205

The injected ripple is:

EQUATION 5-13:

EQUATION 5-14:

In Equation 5-14 and Equation 5-15, it is assumed that

the time constant associated with C14 must be much

greater than the switching period:

EQUATION 5-15:

If the voltage divider resistors RFB1 and RFB2 are in the

k range, then a C14 of 1 nF to 100 nF can easily

satisfy the large time constant requirements.

5.6 Thermal Measurements and Safe

Operating Area (SOA)

Measuring the IC’s case temperature is recommended

to ensure it is within its operating limits. Although this

might seem like a very elementary task, it is easy to get

erroneous results. The most common mistake is to use

the standard thermal couple that comes with a thermal

meter. This thermal couple wire gauge is large, typically

22 gauge, and behaves like a heatsink, resulting in a

lower case measurement.

Two methods of temperature measurement are using a

smaller thermal couple wire or an infrared

thermometer. If a thermal couple wire is used, it must

be constructed of 36-gauge wire or higher (smaller wire

size) to minimize the wire heat-sinking effect. In

addition, the thermal couple tip must be covered in

either thermal grease or thermal glue to make sure that

the thermal couple junction is making good contact with

the case of the IC. Omega brand thermal couple

(5SC-TT-K-36-36) is adequate for most applications.

Wherever possible, an infrared thermometer is

recommended. The measurement spot size of most

infrared thermometers is too large for an accurate

reading on a small form factor ICs. However, an IR

thermometer from Optris has a 1 mm spot size, which

makes it a good choice for measuring the hottest point

on the case. An optional stand makes it easy to hold the

beam on the IC for long periods of time.

The safe operating area (SOA) of the MIC45205 is

shown in Figure 5-6 through Figure 5-10. These

thermal measurements were taken on MIC45205

evaluation board. Since the MIC45205 is an entire

system comprised of switching regulator controller,

MOSFETs and inductor, the part needs to be

considered as a system. The SOA curves will give

guidance to reasonable use of the MIC45205.

SOA curves should only be used as a point of

reference. SOA data was acquired using the MIC45205

evaluation board. Thermal performance depends on

the PCB layout, board size, copper thickness, number

of thermal vias, and actual airflow.

FIGURE 5-6: MIC45205 Power Derating

vs. Airflow (5VIN to 1.5VOUT).

VFB PP

VIN Kdiv

D1D–1

fSW 

-----------------

=

Where:

VIN Power stage input voltage

D Duty cycle

fSW Switching frequency

τ(RFB1//RFB2//RINJ) x C14

RINJ = 10 k, CINJ = 0.1 µF

Kdiv

RFB1//RFB2

RINJ RFB1//RFB2

-----------------------------------------------=

Where:

RINJ 10 k

fSW 

-----------------T



---=1«

85 90 95 100 105 110 115 120 125

MAXIMUM OUTPUT CURRENT (A)

AMBIENT TEMPERATURE(qC)

0 LFM

200 LFM

400 LFM

\ \ AMEIENT TEMPERATURE we)

MIC45205

DS20005798A-page 22  2017 Microchip Technology Inc.

FIGURE 5-7: MIC45205 Power Derating

vs. Airflow (12VIN to 1.5VOUT).

FIGURE 5-8: MIC45205 Power Derating

vs. Airflow (12VIN to 3.3VOUT).

FIGURE 5-9: MIC45205 Power Derating

vs. Airflow (24VIN to 1.5VOUT).

FIGURE 5-10: MIC45205 Power Derating

vs. Airflow (24VIN to 3.3VOUT).

80 85 90 95 100 105 110 115 120

MAXIMUM OUTPUT CURRENT (A)

AMBIENT TEMPERATURE (qC)

0 LFM

200 LFM

400 LFM

80 85 90 95 100 105 110 115 120

MAXIMUM OUTPUT CURRENT (A)

AMBIENT TEMPERATURE (qC)

0 LFM

200 LFM

400 LFM

70 75 80 85 90 95 100 105 110 115 120

MAXIMUM OUTPUT CURRENT (A)

AMBIENT TEMPERATURE (

0 LFM

200 LFM

400 LFM

60 65 70 75 80 85 90 95 100 105 110

MAXIMUM OUTPUT CURRENT (A)

AMBIENT TEMPERATURE (qC)

0 LFM

200 LFM

400 LFM

 2017 Microchip Technology Inc. DS20005798A-page 23

MIC45205

6.0 PCB LAYOUT GUIDELINES

To minimize EMI and output noise, follow these layout

recommendations.

PCB layout is critical to achieve reliable, stable and

efficient performance. A ground plane is required to

control EMI and minimize the inductance in power,

signal and return paths.

Figure 6-1 is optimized from a small form factor point of

view shows top and bottom layer of a four layer PCB. It

is recommended to use mid layer 1 as a continuous

ground plane.

FIGURE 6-1: Top And Bottom Layer of a

Four-Layer Board.

The following guidelines should be followed to insure

proper operation of the MIC45205 module:

6.1 IC

• The analog ground pin (GND) must be connected

directly to the ground planes. Place the IC close

to the point-of-load (POL).

• Use thick traces to route the input and output

power lines.

• Analog and power grounds should be kept

separate and the analog ground (GND) and

power ground (PGND) are internally connected.

6.2 Input Capacitor

• Place the input capacitors on the same side of the

board and as close to the IC as possible.

• Place several vias to the ground plane close to

the input capacitor ground terminal.

• Use either X7R or X5R dielectric input capacitors.

Do not use Y5V or Z5U type capacitors.

• Do not replace the ceramic input capacitor with

any other type of capacitor. Any type of capacitor

can be placed in parallel with the ceramic input

capacitor.

• If a non-ceramic input capacitor is placed in

parallel with the input capacitor, it must be

recommended for switching regulator applications

and the operating voltage.

• In “Hot-Plug” applications, an Electrolytic bypass

capacitor must be used to limit the over-voltage

spike seen on the input supply with power is

suddenly applied. If hot-plugging is the normal

operation of the system, using an appropriate

hot-swap IC is recommended.

6.3 RC Snubber (Optional)

• Depending on the operating conditions, a RC

snubber on the same side of the board can be

used. Place the RC and as close to the SW pin as

possible if needed.

6.4 SW Node

• Do not route any digital lines underneath or close

to the SW node.

• Keep the switch node (SW) away from the

feedback (FB) pin.

6.5 Output Capacitor

• Use a wide trace to connect the output capacitor

ground terminal to the input capacitor ground

terminal.

• Phase margin will change as the output capacitor

value and ESR changes.

• The feedback trace should be separate from the

power trace and connected as close as possible

to the output capacitor. Sensing a long

high-current load trace can degrade the DC load

regulation.

“31(96') xmnxm.

MIC45205

DS20005798A-page 24  2017 Microchip Technology Inc.

6.6 PCB Layout Recommendations

FIGURE 6-2: Top Copper Layer 1.

FIGURE 6-3: Copper Layer2.

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 2017 Microchip Technology Inc. DS20005798A-page 25

MIC45205

FIGURE 6-4: Copper Layer 3.

FIGURE 6-5: Bottom Copper Layer 4.

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MIC45205

DS20005798A-page 26  2017 Microchip Technology Inc.

7.0 SIMPLIFIED PCB DESIGN

RECOMMENDATIONS

7.1 Periphery I/O Pad Layout and

Large Pad for Exposed Heatsink

The board design should begin with copper/metal pads

that sit beneath the periphery leads of a mounted QFN.

The board pads should extend outside the QFN

package edge a distance of approximately 0.20 mm

per side:

Total pad length = 8.00 mm + (0.20 mm per side × 2

sides) = 8.40 mm.

After completion of the periphery pad design, the larger

exposed pads will be designed to create the mounting

surface of the QFN exposed heatsink. The primary

transfer of heat out of the QFN will be directly through

the bottom surface of the exposed heatsink. To aid in

the transfer of generated heat into the PCB, the use of

an array of plated through-hole vias beneath the

mounted part is recommended. The typical via hole

diameter is 0.30 mm to 0.35 mm, with center-to-center

pitch of 0.80 mm to 1.20 mm.

FIGURE 7-1: Package Bottom View vs. PCB Recommended Exposed Metal Trace.

Please note that the exposed metal trace is a “mirror

image” of the package bottom view.

STACKED UF ”W m mmmmm mam m qunER STENCIL EIPENING

 2017 Microchip Technology Inc. DS20005798A-page 27

MIC45205

7.2 Solder Paste Stencil Design

(Recommend Stencil Thickness =

112.5 µm ±12.5 µm)

The solder stencil aperture openings should be smaller

than the periphery or large PCB exposed pads to

reduce any chance of build-up of excess solder at the

large exposed pad area which can result to solder

bridging.

The suggested reduction of the stencil aperture

opening is typically 0.20 mm smaller than exposed

metal trace.

Please note that a critical requirement is to not

duplicate land pattern of the exposed metal trace as

solder stencil opening as the design and dimension

values are different.

FIGURE 7-2: Solder Stencil Opening.

Note that the cyan-colored shaded pad indicates

exposed trace keep out area.

FIGURE 7-3: Stack-Up of Pad Layout and

Solder Paste Stencil.

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MIC45205

DS20005798A-page 28  2017 Microchip Technology Inc.

8.0 EVALUATION BOARD SCHEMATIC AND BOM

FIGURE 8-1: MIC45205YML Evaluation Board Schematic.

TABLE 8-1: BILL OF MATERIALS

Item Part Number Manufacturer Description Quantity

C1 EEE-FK1V221P Panasonic 220 µF/35V, ALE Capacitor (optional) 1

C1X, C6, C9,

C10, C7, C13 — — Open 6

C3 C3216X5R1H106M160AB TDK 10 µF/50V, 1206, X5R, 10%, MLCC 1

C2, C4, C8 GRM188R71H104KA93D Murata 0.1 µF/50V, X7R, 0603, 10%, MLCC 3

C5 C3216X5R0J107M160AB TDK 100 µF/6.3V, X5R, 1206, 20%, MLCC 1

C14 C1608C0G1H222JT TDK 2.2 nF/50V, NP0, 0603, 5%, MLCC 1

C11 GRM1885C1H150JA01D Murata 15 pF/50V, NP0, 0603, 5%, MLCC 3

CON1,CON2,

CON3,CON4 8174 Keystone 15A, 4-Prong Through-Hole Screw

Terminal 4

J1 M50-3500742 Harwin Header 2x7 1

J2, J3, J4,

TP3 – TP5 90120-0122 Molex Header 2 6

JPx1, JPx2 — — Open 2

R1, R10 CRCW0603100K0FKEA Vishay Dale 100 k, 1%, 1/10W, 0603, Thick Film 2

R2, R12, R13,

R16 — — Open 4

R3 CRCW060340K2FKEA Vishay Dale 40.2 k, 1%, 1/10W, 0603, Thick Film 1

R4 CRCW060320K0FKEA Vishay Dale 20 k, 1%, 1/10W, 0603, Thick Film 1

R5 CRCW060311K5FKEA Vishay Dale 11.5 k, 1%, 1/10W, 0603, Thick Film 1

R6 CRCW06038K06FKEA Vishay Dale 8.06 k, 1%, 1/10W, 0603, Thick Film 1

R7 CRCW06034K75FKEA Vishay Dale 4.75 k, 1%, 1/10W, 0603, Thick Film 1

 2017 Microchip Technology Inc. DS20005798A-page 29

MIC45205

R8 CRCW06033K24FKEA Vishay Dale 3.24 k, 1%, 1/10W, 0603, Thick Film 1

R9 CRCW06031K91FKEA Vishay Dale 1.91 k, 1%, 1/10W, 0603, Thick Film 1

R11 CRCW060349K9FKEA Vishay Dale 49.9 k, 1%, 1/10W, 0603, Thick Film 1

R14 CRCW060310K0FKEA Vishay Dale 10 k, 1%, 1/10W, 0603, Thick Film 1

R15 CRCW06031K37FKEA Vishay Dale 1.37 k, 1%, 1/10W, 0603, Thick Film 1

R17, R18,

R19 RCG06030000Z0EA Vishay Dale 0 Resistor, 1%, 1/10W, 0603, Thick

Film 3

TP6 – TP9,

JPx3, JPx4 1502-2 Keystone Single-End, Through-Hole Terminal 6

U1 MIC45205-1YMP Microchip 26V/6A DC/DC Power Module 1

MIC45205-2YMP

TABLE 8-1: BILL OF MATERIALS (CONTINUED)

Item Part Number Manufacturer Description Quantity

NNN Pbrfree JEDEC designamr( )

MIC45205

DS20005798A-page 30  2017 Microchip Technology Inc.

9.0 PACKAGING INFORMATION

9.1 Package Marking Information

Example

52-Pin QFN*

XXX

XXXXX-XXXX

YYWW

MIC

45205-1YMP

1308

Legend: XX...X Product code or customer-specific information

Y Year code (last digit of calendar year)

YY Year code (last 2 digits of calendar year)

WW Week code (week of January 1 is week ‘01’)

NNN Alphanumeric traceability code

Pb-free JEDEC® designator for Matte Tin (Sn)

*This package is Pb-free. The Pb-free JEDEC designator ( )

can be found on the outer packaging for this package.

, , Pin one index is identified by a dot, delta up, or delta down (triangle

mark).

Note: In the event the full Microchip part number cannot be marked on one line, it will

be carried over to the next line, thus limiting the number of available

characters for customer-specific information. Package may or may not include

the corporate logo.

Underbar (_) and/or Overbar () symbol may not be to scale.

TITLE 5: LEAD EZQFN Bxsnm PACKAGE (Module) OUTLINE 5‘ RECOMMENDED LAND PATTERN DRAWING if H3QFNHH’52LD’PL’1 UNIT MM Lead Frame copper Lead Finish Matte Tm PIN 1 DDT PIN# 1 IDENFICATIDN CHAMFER 0250x45° BY MARKING E : IIIQEIII an ”SHIQHHH: ”gin: M Bottom \/iew NEITEi 1, 2, 3 NEITE‘ I, 2, 3 m mm uni a eJ Side View NEITEi 1, E, 3

 2017 Microchip Technology Inc. DS20005798A-page 31

MIC45205

52-Lead 8 mm x 8 mm H3QFN Package Outline and Recommended Land Pattern

Recommended Land Pattern NEITE‘ 4, 5, 6 SmpUPQd LP F444*$::%:a .n HUME DUE M. :l F7233 frame . v v v v v v C 000.04 0.6.. '%%&&éwﬁk :‘z’:’:‘:’:3:133:’:’:‘:3:3: iﬁﬁﬁﬁﬁaﬁﬁ 0.99.9 .9...9 ,—w “E Mﬂﬂﬂﬁﬂﬁgfggﬁ EXPDSED M‘ TAL TRACE 9 9'9'.'9' '9‘1 99 'zozom: «m. .‘9’9’.’.’9’9 9.9.9.... o . .9...9,.,.,99.9..,.,9,9. ...<99..... q....9.9:.:.:9:.:.:9:.:.:.:="" 9.999.9«999999="" u="" 31:="" seilder="" stencil="" iiipeninu="">

MIC45205

DS20005798A-page 32  2017 Microchip Technology Inc.

Note: For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging.

Recommended Land Pattern SWpUFPd LP 1 9’0 O... 9.9 coco. ’o’o‘o’o'o’o 9,0,0 mum ,9 0 0.9.0.3... o. T I T I o «@222 ~LYZA 7 q’ o 0 0:0 0,. 9.9 o O o ’0 ”W HQQ¥EﬂE .,.. Mm “www.mmm" STACKED UP NDTE: 1‘ MAX PACKAGE WARPAGE IS 005 MM 3 MAX ALLDWABLE BURR IS UD76MM IN ALL DIRECTIDNS 3‘ PIN #1 IS DN TDP WILL BE LASER MARKED 4‘ BLACK CIRCLES IN LAND PATTERN REPRESENT THERMAL VIA, RECDMMENDED SIZE IS 0‘30’0‘35MM AT UBUmm PITCH & SHDULD BE CDNNECTED TD [3ND EDR MAXIMUM PEREDRMANCE‘ 5‘ GREEN RECTANGLES (SHADED AREA) REPRESENT SDLDER STENCIL DPENING DN EXPDSED PAD AREA‘ 6‘ CYAN CDLDRED S TADED PAD REPRESENT :XPESED TRACE KEEP HUT AREA

 2017 Microchip Technology Inc. DS20005798A-page 33

MIC45205

Note: For the most current package drawings, please see the Microchip Packaging Specification located at

http://www.microchip.com/packaging.

JZLIIQ T" LE :i O O ’ a ‘ [E E «E'wﬁﬂmE—Qﬂﬂﬂﬂﬂif, EXPDSED METAL TRACE 2134- use - ‘— .0... Ann m VA E_ $393939: 3‘ .9...0.0.G .‘ .060 930:. 9‘... 9‘0, n , 'MT Z )6) 7L. T 7 I SDLDER STENCIL DPENING STACKED UP WK: 1 MAx PACKAGE wARPAnE IS nus MM 2 MAx ALLDVAHLE BURR IS an7sMM IN ALL DIRECHDNS 3 PIN In [S UN mP wILL BE LASER MARKED A BLACK CIRCLES 1N LAND PAYYERN REPRESENY mERMAL le, RECuMMENnEn SIZE IS naurnssm, AI oEDnn PHCH I. SHEIULD BE CuNNECTEn m END FDR MAXIMUM PERruRMANcE. 5. GREEN RECTANGLES (SHADED AREA) REPRESENY SCILDER SYENCIL DFENING EIN EXPDSED PAD AREA 6. chN EDLDRED SHADE): PAD REFRESENY EXPDSED YRACE KEEP um AREA.

MIC45205

DS20005798A-page 34  2017 Microchip Technology Inc.

Thermally Enhanced Land Pattern

FIGURE 9-1: Exposed Metal Trace.

FIGURE 9-2: Solder Stencil Opening.

FIGURE 9-3: Stack-Up of Pad Layout and

Solder Paste Stencil and Notes.

 2017 Microchip Technology Inc. DS20005798A-page 35

MIC45205

APPENDIX A: REVISION HISTORY

Revision A (June 2017)

• Converted Micrel document MIC45205 to Micro-

chip data sheet DS20005798A.

• Minor text changes throughout.

• Updated maximum output voltage from 5.5V to

0.85 x VIN in Features and General Description.

MIC45205

DS20005798A-page 36  2017 Microchip Technology Inc.

NOTES:

PART NO. _x 41x

 2017 Microchip Technology Inc. DS20005798A-page 37

MIC45205

PRODUCT IDENTIFICATION SYSTEM

To order or obtain information, e.g., on pricing or delivery, contact your local Microchip representative or sales office.

Examples:

a) MIC45205-1YMP-T1: 26V/6A DC/DC Power

Module, HyperLight Load,

–40°C to +125°C, 52-Lead

8 mm x 8 mm x 3 mm QFN,

100/Reel

b) MIC45205-1YMP-TR: 26V/6A DC/DC Power

Module, HyperLight Load,

–40°C to +125°C, 52-Lead

8 mm x 8 mm x 3 mm QFN,

1,500/Reel

c) MIC45205-2YMP-T1: 26V/6A DC/DC Power

Module, Hyper Speed Control,

–40°C to +125°C, 52-Lead

8 mm x 8 mm x 3 mm QFN,

100/Reel

d) MIC45205-2YMP-TR: 26V/6A DC/DC Power

Module, Hyper Speed Control,

–40°C to +125°C, 52-Lead

8 mm x 8 mm x 3 mm QFN,

1,500/Reel

PART NO. XX

Package

Device

Device: MIC45205: 26V/6A DC/DC Power Module

Features: 1 = HyperLight Load

2 = Hyper Speed Control

Temperature: Y = –40°C to +125°C

Package: MP = 52-Lead 8 mm x 8 mm x 3 mm QFN

Media Type: T1 = 100/Reel

TR = 1,500/Reel

–X

Temperature

Note 1: Tape and Reel identifier only appears in the

catalog part number description. This identifier is

used for ordering purposes and is not printed on

the device package. Check with your Microchip

Sales Office for package availability with the

Tape and Reel option.

–XX

Media Type

Features

MIC45205

DS20005798A-page 38  2017 Microchip Technology Inc.

NOTES:

YSTEM

 2017 Microchip Technology Inc. DS20005798A-page 39

Information contained in this publication regarding device

applications and the like is provided only for your convenience

and may be superseded by updates. It is your responsibility to

ensure that your application meets with your specifications.

MICROCHIP MAKES NO REPRESENTATIONS OR

WARRANTIES OF ANY KIND WHETHER EXPRESS OR

IMPLIED, WRITTEN OR ORAL, STATUTORY OR

OTHERWISE, RELATED TO THE INFORMATION,

INCLUDING BUT NOT LIMITED TO ITS CONDITION,

QUALITY, PERFORMANCE, MERCHANTABILITY OR

FITNESS FOR PURPOSE. Microchip disclaims all liability

arising from this information and its use. Use of Microchip

devices in life support and/or safety applications is entirely at

the buyer’s risk, and the buyer agrees to defend, indemnify and

hold harmless Microchip from any and all damages, claims,

suits, or expenses resulting from such use. No licenses are

conveyed, implicitly or otherwise, under any Microchip

intellectual property rights unless otherwise stated.

Trademarks

The Microchip name and logo, the Microchip logo, AnyRate, AVR,

AVR logo, AVR Freaks, BeaconThings, BitCloud, CryptoMemory,

CryptoRF, dsPIC, FlashFlex, flexPWR, Heldo, JukeBlox, KEELOQ,

KEELOQ logo, Kleer, LANCheck, LINK MD, maXStylus,

maXTouch, MediaLB, megaAVR, MOST, MOST logo, MPLAB,

OptoLyzer, PIC, picoPower, PICSTART, PIC32 logo, Prochip

Designer, QTouch, RightTouch, SAM-BA, SpyNIC, SST, SST

Logo, SuperFlash, tinyAVR, UNI/O, and XMEGA are registered

trademarks of Microchip Technology Incorporated in the U.S.A.

and other countries.

ClockWorks, The Embedded Control Solutions Company,

EtherSynch, Hyper Speed Control, HyperLight Load, IntelliMOS,

mTouch, Precision Edge, and Quiet-Wire are registered

trademarks of Microchip Technology Incorporated in the U.S.A.

Adjacent Key Suppression, AKS, Analog-for-the-Digital Age, Any

Capacitor, AnyIn, AnyOut, BodyCom, chipKIT, chipKIT logo,

CodeGuard, CryptoAuthentication, CryptoCompanion,

CryptoController, dsPICDEM, dsPICDEM.net, Dynamic Average

Matching, DAM, ECAN, EtherGREEN, In-Circuit Serial

Programming, ICSP, Inter-Chip Connectivity, JitterBlocker,

KleerNet, KleerNet logo, Mindi, MiWi, motorBench, MPASM, MPF,

MPLAB Certified logo, MPLIB, MPLINK, MultiTRAK, NetDetach,

Omniscient Code Generation, PICDEM, PICDEM.net, PICkit,

PICtail, PureSilicon, QMatrix, RightTouch logo, REAL ICE, Ripple

Blocker, SAM-ICE, Serial Quad I/O, SMART-I.S., SQI,

SuperSwitcher, SuperSwitcher II, Total Endurance, TSHARC,

USBCheck, VariSense, ViewSpan, WiperLock, Wireless DNA, and

ZENA are trademarks of Microchip Technology Incorporated in the

U.S.A. and other countries.

SQTP is a service mark of Microchip Technology Incorporated in

the U.S.A.

Silicon Storage Technology is a registered trademark of Microchip

Technology Inc. in other countries.

GestIC is a registered trademark of Microchip Technology

Germany II GmbH & Co. KG, a subsidiary of Microchip Technology

Inc., in other countries.

All other trademarks mentioned herein are property of their

respective companies.

ISBN: 978-1-5224-1845-0

Note the following details of the code protection feature on Microchip devices:

• Microchip products meet the specification contained in their particular Microchip Data Sheet.

• Microchip believes that its family of products is one of the most secure families of its kind on the market today, when used in the

intended manner and under normal conditions.

• There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our

knowledge, require using the Microchip products in a manner outside the operating specifications contained in Microchip’s Data

Sheets. Most likely, the person doing so is engaged in theft of intellectual property.

• Microchip is willing to work with the customer who is concerned about the integrity of their code.

• Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not

mean that we are guaranteeing the product as “unbreakable.”

Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our

products. Attempts to break Microchip’s code protection feature may be a violation of the Digital Millennium Copyright Act. If such acts

allow unauthorized access to your software or other copyrighted work, you may have a right to sue for relief under that Act.

Microchip received ISO/TS-16949:2009 certification for its worldwide

headquarters, design and wafer fabrication facilities in Chandler and

Tempe, Arizona; Gresham, Oregon and design centers in California

and India. The Company’s quality system processes and procedures

are for its PIC® MCUs and dsPIC® DSCs, KEELOQ® code hopping

devices, Serial EEPROMs, microperipherals, nonvolatile memory and

analog products. In addition, Microchip’s quality system for the design

and manufacture of development systems is ISO 9001:2000 certified.

QUALITYMANAGEMENTS

YSTEM

CERTIFIEDBYDNV

== ISO/TS16949==

6‘ ‘MICRDCHIP

DS20005798A-page 40  2017 Microchip Technology Inc.

AMERICAS

Corporate Office

2355 West Chandler Blvd.

Chandler, AZ 85224-6199

Tel: 480-792-7200

Fax: 480-792-7277

Technical Support:

http://www.microchip.com/

support

Web Address:

www.microchip.com

Atlanta

Duluth, GA

Tel: 678-957-9614

Fax: 678-957-1455

Austin, TX

Tel: 512-257-3370

Boston

Westborough, MA

Tel: 774-760-0087

Fax: 774-760-0088

Chicago

Itasca, IL

Tel: 630-285-0071

Fax: 630-285-0075

Dallas

Addison, TX

Tel: 972-818-7423

Fax: 972-818-2924

Detroit

Novi, MI

Tel: 248-848-4000

Houston, TX

Tel: 281-894-5983

Indianapolis

Noblesville, IN

Tel: 317-773-8323

Fax: 317-773-5453

Tel: 317-536-2380

Los Angeles

Mission Viejo, CA

Tel: 949-462-9523

Fax: 949-462-9608

Tel: 951-273-7800

Raleigh, NC

Tel: 919-844-7510

New York, NY

Tel: 631-435-6000

San Jose, CA

Tel: 408-735-9110

Tel: 408-436-4270

Canada - Toronto

Tel: 905-695-1980

Fax: 905-695-2078

ASIA/PACIFIC

Asia Pacific Office

Suites 3707-14, 37th Floor

Tower 6, The Gateway

Harbour City, Kowloon

Hong Kong

Tel: 852-2943-5100

Fax: 852-2401-3431

Australia - Sydney

Tel: 61-2-9868-6733

Fax: 61-2-9868-6755

China - Beijing

Tel: 86-10-8569-7000

Fax: 86-10-8528-2104

China - Chengdu

Tel: 86-28-8665-5511

Fax: 86-28-8665-7889

China - Chongqing

Tel: 86-23-8980-9588

Fax: 86-23-8980-9500

China - Dongguan

Tel: 86-769-8702-9880

China - Guangzhou

Tel: 86-20-8755-8029

China - Hangzhou

Tel: 86-571-8792-8115

Fax: 86-571-8792-8116

China - Hong Kong SAR

Tel: 852-2943-5100

Fax: 852-2401-3431

China - Nanjing

Tel: 86-25-8473-2460

Fax: 86-25-8473-2470

China - Qingdao

Tel: 86-532-8502-7355

Fax: 86-532-8502-7205

China - Shanghai

Tel: 86-21-3326-8000

Fax: 86-21-3326-8021

China - Shenyang

Tel: 86-24-2334-2829

Fax: 86-24-2334-2393

China - Shenzhen

Tel: 86-755-8864-2200

Fax: 86-755-8203-1760

China - Wuhan

Tel: 86-27-5980-5300

Fax: 86-27-5980-5118

China - Xian

Tel: 86-29-8833-7252

Fax: 86-29-8833-7256

ASIA/PACIFIC

China - Xiamen

Tel: 86-592-2388138

Fax: 86-592-2388130

China - Zhuhai

Tel: 86-756-3210040

Fax: 86-756-3210049

India - Bangalore

Tel: 91-80-3090-4444

Fax: 91-80-3090-4123

India - New Delhi

Tel: 91-11-4160-8631

Fax: 91-11-4160-8632

India - Pune

Tel: 91-20-3019-1500

Japan - Osaka

Tel: 81-6-6152-7160

Fax: 81-6-6152-9310

Japan - Tokyo

Tel: 81-3-6880- 3770

Fax: 81-3-6880-3771

Korea - Daegu

Tel: 82-53-744-4301

Fax: 82-53-744-4302

Korea - Seoul

Tel: 82-2-554-7200

Fax: 82-2-558-5932 or

82-2-558-5934

Malaysia - Kuala Lumpur

Tel: 60-3-6201-9857

Fax: 60-3-6201-9859

Malaysia - Penang

Tel: 60-4-227-8870

Fax: 60-4-227-4068

Philippines - Manila

Tel: 63-2-634-9065

Fax: 63-2-634-9069

Singapore

Tel: 65-6334-8870

Fax: 65-6334-8850

Taiwan - Hsin Chu

Tel: 886-3-5778-366

Fax: 886-3-5770-955

Taiwan - Kaohsiung

Tel: 886-7-213-7830

Taiwan - Taipei

Tel: 886-2-2508-8600

Fax: 886-2-2508-0102

Thailand - Bangkok

Tel: 66-2-694-1351

Fax: 66-2-694-1350

EUROPE

Austria - Wels

Tel: 43-7242-2244-39

Fax: 43-7242-2244-393

Denmark - Copenhagen

Tel: 45-4450-2828

Fax: 45-4485-2829

Finland - Espoo

Tel: 358-9-4520-820

France - Paris

Tel: 33-1-69-53-63-20

Fax: 33-1-69-30-90-79

France - Saint Cloud

Tel: 33-1-30-60-70-00

Germany - Garching

Tel: 49-8931-9700

Germany - Haan

Tel: 49-2129-3766400

Germany - Heilbronn

Tel: 49-7131-67-3636

Germany - Karlsruhe

Tel: 49-721-625370

Germany - Munich

Tel: 49-89-627-144-0

Fax: 49-89-627-144-44

Germany - Rosenheim

Tel: 49-8031-354-560

Israel - Ra’anana

Tel: 972-9-744-7705

Italy - Milan

Tel: 39-0331-742611

Fax: 39-0331-466781

Italy - Padova

Tel: 39-049-7625286

Netherlands - Drunen

Tel: 31-416-690399

Fax: 31-416-690340

Norway - Trondheim

Tel: 47-7289-7561

Poland - Warsaw

Tel: 48-22-3325737

Romania - Bucharest

Tel: 40-21-407-87-50

Spain - Madrid

Tel: 34-91-708-08-90

Fax: 34-91-708-08-91

Sweden - Gothenberg

Tel: 46-31-704-60-40

Sweden - Stockholm

Tel: 46-8-5090-4654

UK - Wokingham

Tel: 44-118-921-5800

Fax: 44-118-921-5820

Worldwide Sales and Service

11/07/16

Microchip Technology 的 MIC45205-1,2 规格书

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