UC1103

DESCRIPTION

The UTC UC1103 is a primary control unit for switch mode

charger and adapter applications. The controlled variable is

transferred by an auxiliary winding from the secondary to the

primary side. The device integrates PWM controller to enhance the

performance of discontinuous conduction mode (DCM) flyback

converters.

The UTC UC1103 operates in primary-side sensing and

regulation. Opto-coupler and TL431 could be eliminated. It also

provides off-time modulation to linearly decrease PWM frequency

under light-load conditions so that low standby power can be

achieved.

The UTC UC1103 achieves high precision CV/CC regulation

and high power efficiency. It offers comprehensive protection

coverage with auto-recovery features including Cycle-by-cycle

current limiting, V DD over voltage protection, V DD clamp, OTP,

leading edge blanking, V DD under voltage lockout, etc.

FEATURES

* High voltage startup

* ±5% constant voltage regulation at universal AC input

* High precision constant current regulation at universal AC input

* Primary side control without TL431 and opto-coupler

* Programmable CV and CC regulation

* Programmable cable compensation in CV mode

* Flyback topology in DCM operation

* Frequency hopping to reduce system EMI

* Driver MOSFET switch

* Built-in leading edge blanking

* Built-in primary winding inductance

compensation

* Gate output maximum voltage clamped at 15V

* Cycle-by-cycle current limiting

* Over voltage protection

* V DD under-voltage lockout

规格书UC1103