HT7939_16 Datasheet, PDF (1/12 Pages) Holtek Semiconductor Inc – High Current and Performance White LED Driver

HT7939
High Current and Performance White LED Driver
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: 0.1mA (typ.) with V_EN 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
Applications
· Display Backlighting
- Automatic
- DVD player
- Digital photo frame
- Handheld computer
· LED lighting
General Description
The HT7939 is a high efficiency boost converter for driv-
ing White LEDs using current mode operation. The de-
vice 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 feed-
back voltage of 0.2V to minimise power losses in the re-
sistor which improves efficiency. The Over-voltage
function prevents damage to the IC by turning off the
converter when the LED load is open circuit.
The device includes over current protection, over tem-
perature protection and under voltage protection pre-
venting damage to the device when the output is
overloaded.
Selection Table
Part No.
HT7939
Package
SOT23-6
Marking
7939
Rev 1.60
1
June 25, 2016