US3602G-S08-R datasheet(6/7 Pages) UTC

6 / 7 page

US3602

Preliminary

CMOS IC

UNISONICTECHNOLOGIESCO.,LTD

6 of 7

www.unisonic.com.tw

QW-R502-985.b



FUNCTION DESCRIPTION(Cont.)

Operation Switching Frequency

The UTC US3602 is designed to work in DCM flyback topology and no external loop compensation component is

required while maintaining stability. The maximum duty cycle is limited to 50%. The maximum switching frequency

should be set to less than 100KHz and the minimum switching frequency should be set to more than 20KHz. The

maximum and minimum switching frequency is limited in UTC US3602 to ensure the stability of system.

The switching frequency can be set by the formula:

LED

Where, LP is the primary winding inductance of transformer.

Protection Control

Good power supply system reliability is achieved with its comprehensive protection features including VCC

over-voltage protection, VCC Clamp, GATE Clamp, Cycle-by-cycle current limiting, LED short circuit protection, LED

open circuit protection, leading edge blanking, OTP and UVLO, etc.

VCC is supplied by transformer auxiliary winding output. The output of UTC US3602 is shutdown when VCC drops

below VTH(OFF) and the power converter enters power on start-up sequence thereafter.

US3602G-S08-R Arkusz danych(PDF) 6 Page - Unisonic Technologies