HT7939A Datasheet PDF | Holtek Semiconductor

Holtek Semiconductor HT7939A

The HT7939A is a high efficiency boost converter for driving multiple 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 resistor power losses and thus improving efficiency.

Part No.	HT7939A
Datasheet	HT7939A Download
Manufacturer	Holtek Semiconductor
Description	High Current and Performance White LED Driver
Buy	Stock & Price

APPLICATIONS

● Display backlighting –– Automatic –– DVD player –– Digital photo frame –– Handheld computer

GENERAL DESCRIPTION

The HT7939A has a dimming frequency of up to 200kHz, which has excellent linear performance over this dimming frequency range. The over voltage function prevents device damage by turning off the converter should the LED load become open circuit. The device also includes over current protection, over temperature protection and under voltage protection preventing damage to the device should the output be overloaded. Selection Guide Part No. HT7939A-1 HT7939A-2 Package SOT23-6 Note: Both lead free and green compound devices are available. Marking 39A-1 (OVP=17.6V) 39A-2 (OVP=32.0V) Rev. 1.30 1 August 04, 2018 Block Diagram FB O VP P ro te c t O VP 1 7 .6 V (3 9 A -1 ) 3 2 .0 V (3 9 A -2 ) R am p 1 .2 M H z O SC O TP SR R Q V IN U V L O = 2 .1 V SW HT7939A BG EN GND Pin Assignment SOT23-6 VIN 6 OVP EN 54 39A-X Top View 1 23 SW GND FB Pin Descriptin PIN No. PIN Name

DESCRIPTION

1 SW Switching pin.