The OC5257 is a continuous inductor current on-mode step-down LED constant current driver used to drive one or more LED strings. The OC5257 operates from 4.8V to 65V and provides adjustable output current up to 800mA. Depending on the input voltage and external components, the OC5257 can drive LEDs up to tens of watts.
The OC5257 has a built-in power switch with high-side current-sense circuitry, and a dimming foot DIM that is compatible with PWM and analog dimming. When the DIM pin voltage is lower than 0.3v, the output is turned off and enters the standby state.
The OC5257 has a built-in over-temperature protection circuit, and when the chip reaches the over-temperature protection point and enters the over-temperature protection mode, the output current gradually decreases to improve system reliability.
The OC5257 uses a patented circuit architecture to ensure that the output current is free of overshoot when operating at low dropout voltages, improving the operating life of LEDs, and the OC5257 uses a patented constant current circuit with excellent load regulation and linear regulation.
The OC5257 is available in a SOT23-5 package.

Applications
LED Backup Lights, Signal Lights
Low-voltage LED spotlights instead of halogen lamps
Automotive lighting