Texas Instruments's LM5117 is a synchronous buck controller intended for step-down regulator applications from a high voltage or widely varying input supply. The control method is based upon current mode control utilizing an emulated current ramp. Current mode control provides inherent line feed-forward, cycle-by-cycle current limiting and ease of loop compensation. The use of an emulated control ramp reduces noise sensitivity of the pulse-width modulation circuit, allowing reliable control of very small duty cycles necessary in high input voltage applications.
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- Emulated peak current mode control
- Wide operating range from 5.5 V to 65 V
- Robust 3.3 A peak gate drives
- Adaptive dead-time output driver control
- Free-run or synchronizable clock up to 750 kHz
- Optional diode emulation mode
- Programmable output from 0.8 V
- Precision 1.5% voltage reference
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- Analog current monitor
- Programmable current limit
- Hiccup mode over current protection
- Programmable soft-start and tracking
- Programmable line under-voltage lockout
- Programmable switch-over to external bias supply
- Thermal shutdown
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