MAX8847Y
Description
The MAX8847Y/MAX8847Z negative charge pumps drive up to 6 white LEDs with regulated constant current for display backlight applications. By utilizing an inverting charge pump and extremely low-dropout adaptive current regulators, these ICs achieve very high efficiency over the full 1-cell Li+ battery voltage range even with large LED forward voltage mismatch. The 1MHz fixedfrequency switching allows for tiny external ponents. The regulation scheme is optimized to ensure low EMI and low input ripple. The MAX8847Y/MAX8847Z include thermal shutdown, open- and short-circuit protection. The MAX8847Y/MAX8847Z support independent LED on/off and dimming control. The MAX8847Z has PWM dimming control for LED1- LED6. The MAX8847Y has PWM dimming control for LED1- LED4 and serial-pulse dimming control for LED5 and LED6. The serial-pulse dimming ranges are pseudo-logarithmic from 24m A to 0.1m A and off in 32 steps. All devices include a temperature derating function to safely allow bright...
