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HT7L4091

Universal Step-Down PWM Control

For High Brightness LED Lighting Control

BJT Power Supply Application Circuit

The application circuit uses a BJT to supply the device power to obtain better efficiency.

Zin

BJT

CS

GND

RT

LD

C7

�C

EMI

Lc

Lc

Ca1

Ca�

C1

0.1uF

400V

1uF

50V

0.1uF

L

D1

MOSFET

Rcs

5�F

��uF

400V

If frequency jittering is considered to reduce EMI an optional 5pF CT may be used to stabilise the

effect.

For more details refer to the application note.