HT7939 -- High Current and Performance White LED Driver

　　General Description

　　The HT7939 is a high efficiency boost converter for driving White LEDs using current mode operation. The device is designed to drive up to 39 White LEDs from a 5V power supply. The White LED current is setup using an external current setting resistor, which has a low feedback voltage of 0.2V to minimise power losses in the resistor which improves efficiency. The Over-voltage function prevents damage to the IC by turning off the converter when the LED load is open circuit.

　　Features

　　Input range from 2.6V~5.5V

　　Built-in Power MOSFET

　　Can drive up to 39 White LEDs with a 5V input

　　Low standby current: 0.1uA (typ.) with VEN low

　　Integrated Over-voltage, Over-temperature and Over-current protection circuits

　　Under voltage lock-out protection

　　1.2MHz fixed switching frequency

　　High efficiency - up to 90%

　　6-pin SOT23-6 package