HT7936A/HT7936B -- White LED Step-up Charge Pump Converter

　　General Description

　　The HT7936A and HT7936B are charge-pump type DC-DC step-up converter devices, which can generate regulated fixed output voltages of 5.0V and 4.5V. Their high degree of functional integration requires only the addition of three external capacitors, namely a flying capacitor and an input and output capacitor, to implement a full step-up conversion function.

　　The devices have the additional benefit of an integrated soft start function to reduce the level of in-rush current during device power on. The operating voltage range is from 2.8V to the full output voltage value, VOUT.

　　Features

　　Input voltage range: 2.8V to VOUT

　　Driving current: 110mA (HT7936A), 150mA (HT7936B)

　　Fixed output voltage: 5V (HT7936A), 4.5V (HT7936B)

　　Oscillator frequency: 1MHz

　　Soft start function, current limit, short circuit protection

　　Small outline SOT23-6 package