This design was developed to minimize the current spikes coming out of an electronic transformer to less than 5A, which is a typical transformer rating, when driving an LED MR16 circuit. The off the shelf LED MR16 solutions exhibit spikes that significantly exceed a transformers maximum rated output current which will degrade the reliability of the transformer and reduce its operating lifetime. T…
The LM3450A evaluation board is designed to provide an AC to LED solution for a 30 W LED load. Specifically, it takes an AC mains input and converts it to a constant current output of 700 mA for a series string of 1 to 13 LEDs (maximum LED stack voltage of 45 V). There are two assembly versions designed to operate from two different nominal AC input voltages, 120 VAC or 230 VAC.
* For Constant Current, the board must be modified as described on page 8 of the user guide. * Streetlight applications require that the power supply designed to power an LED lamp must have high efficiency and at least an equivalent lifetime in order to guarantee maintenance-free operation during the life of the LED.
Whenever a lighting application, such as street lighting for example, requires an elevated number of LEDs, there are basically two solutions: the first is to connect all the diodes in series in a single "string"; the second is to place several strings in parallel with fewer elements in each one.
This evaluation board is designed around an L6902D-based DC-DC converter with dimming interface. The board implements both of two well known dimming methods: - Analog current control - Average current control by PWM
* The eval board must be modified for 350mA output. The Transformer/Dual inductor and sense resistor(s). This circuit is intended for driving high power LEDs, such as the Cree XLAMP™ series, Lumileds Luxeon™ Rebel and K2 and OSRAM, Golden and Platinum Dragon™ as well as the OSTAR™.
The ZXSC400, although designed for small LEDs in LCD backlighting, is sufficiently flexible to provide an efficient 1W solution producing a nominal 350mA constant current source from 2 NiMH or NiCd cells.
This design note shows a typical ZXSC310 LED driver circuit for a solar power garden light. The input voltage ranges from 1.7V to 2.5V with a maximum output current of 160mA at 2.4V input.
The ZXLD1350 is a continuous mode inductive step-down converter, designed for driving single or multiple series connected LEDs efficiently from a voltage source higher than the LED voltage. The device operates from an input supply between 7V and 30V and provides an externally adjustable output current of up to 350mA.
This application note presents a low-cost driver for LEDs that is compatible with TRIAC phase-control dimmers. The design gives luminaire manufacturers a low-cost, commonly available dimming option for home fixtures. A side benefit is that, when not wired to a dimmer, the unit's power factor is over 0.9. The design is based on the L6562A transitionmode PFC controller driving a single stage PFC-fl…