A8509
Overview
The A8509 is a multi-output white LED driver for backlighting LCD panels. It integrates a current-mode boost controller and four individual current sinks.
- Four integrated high current sinks for LED strings; can be tied together for even higher currents
- Fixed frequency current mode control with integrated gate driver / boost controller; powerful gate driver to drive an external N-channel MOSFET allows significant scaling capability on the number of LEDs per string
- Parallel operation with one boost controller (master) and up to three additional slave controllers; can run up to 16 strings of LEDs while populating only a single master boost regulator
- Active current sharing between LED strings for 0.7% accuracy and 0.8% matching
- Wide input voltage range: 9 to 40 V
- Internal bias supply for single-supply operation (typically VIN = 12 or 24 V)
- Separate Enable and PWM pins as interface for Enable and PWM Dimming functions
- FSET / SYNC function to either set the boost converter switching frequency or synchronize at up to 800 kHz
- Protection Features ▫ Open or shorted LED pin protection ▫ Open Schottky protection ▫ Pulse-by-pulse current limit ▫ Overtemperature protection (OTP) PACKAGES (Not to scale)
