HT7938 Overview
HT7938 is high efficiency boost converter with constant current output to provide backlight in handheld devices. Series connection of LEDs provides constant identical LED currents resulting in uniform brightness. The continuous LED current is set with FB pin regulated voltage across an external sense resistor (RFB) connected from that pin to ground.
HT7938 Key Features
- Efficiency up to 85% at VIN=3.6V, 9LEDs
- Tiny inductor and capacitors
- Up to 9 strings White-LED
- Tiny 6-lead SOT23-6 package
- Built in OVP, OCP, OTP, UVLO protection
- 1.2MHz fixed switching frequency
- Low Standby Current: 0.1mA, VEN=0V (typ.)
- Matches LED current