BCD Semiconductor Manufacturing Limited AP3606
The AP3606 and AP3607 are step-up DC-DC converters based on 1x/1.5x charge pump and low dropout current sink, which helps them maintain the highest efficiency. The AP3606 is specially designed to drive up to 4 WLEDs in backlight display while the AP3607 is designed for 6 WLEDs. These devices provide up to 20mA current for each WLED.GENERAL DESCRIPTION
There are totally 16 steps of current control, which is achieved through a digital pulse dimming function on EN pin. Additionally, 1MHz high switching frequency enables the use of small external capacitors. Internal soft-start circuitry prevents excessive inrush current during start-up and mode transition. The supply voltage ranges of AP3606 and AP3607 are from 2.7V to 5.5V which make them ideally suit for applications powered by Li-ion battery. These ICs are available in the tiny package of QFN-3×3-16.FEATURES
● Regulated Output Current with ±3% Matching● Drives up to 4 WLEDs at 20mA Each (AP3606) Drives up to 6 WLEDs at 20mA Each (AP3607)
● 16 Steps Brightness Control Using Pulse Signal Dimming
● Wide Operating Voltage Range: 2.7V to 5.5V
● High Operating Frequency: 1MHz
● Auto 1x/1.5x Charge Pump Mode Selection
● Built-in Soft-start
● Output Over Voltage Protection
● Built-in UVLO
● Built-in OTSD
● Operating Temperature Range: -40°C to 85°C
APPLICATIONS
● Mobile Phone● PDA
● MP3/4 QFN-3×3-16 Figure 1.