UNISONIC TECHNOLOGIES CO., LTD

USRB01A

Preliminary

LINEAR INTEGRATED CIRCUIT

www.unisonic.com.tw

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Copyright © 2016 Unisonic Technologies Co., Ltd

Ver.a

HIGH PRECISION CC/CV

PRIMARY SIDE SWITCH



DESCRIPTION

The UTC USRB01A is a primary controller for charger and

adapter applications. The controlled variable is transferred by an

auxiliary winding from the secondary to the primary side. The

device uses Pulse Frequency Modulation (PFM) method to build

discontinuous conduction mode (DCM) flyback power supplies.

The UTC USRB01A operates in primary-side sensing and

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

eliminates the need of loop compensation circuitry while

maintaining stability.

The UTC USRB01A 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, output over voltage protection,

lockout, etc.



FEATURES

SOP-8

* ±5% constant voltage regulation at universal AC input

* Primary side control without TL431 and opto-coupler

* High precision constant current regulation at universal AC

input

* Programmable CV and CC regulation

* Eliminates control loop compensation circuitry

* Flyback topology in DCM operation

* Random frequency modulation to reduce system EMI

* Built-in power NPN

* Programmable cable drop compensation

* Built-in leading edge blanking

* Built-in primary winding inductance compensation

* Open circuit protection

* Output over voltage protection

* Short circuit protection

* Over temperature protection



ORDERING INFORMATION

Ordering Number

Package

Packing

USRB01AG-S08-R

SOP-8

Tape Reel