UNISONIC TECHNOLOGIES CO., LTD

USRB02

Preliminary

LINEAR INTEGRATED CIRCUIT

www.unisonic.com.tw

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Copyright © 2015 Unisonic Technologies Co., Ltd

QW-R103-087.a

HIGH PRECISION CC/CV

PRIMARY SIDE SWITCH



DESCRIPTION

The UTC USRB02 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 operates in Pulse Frequency Modulation (PFM) in CC

mode as well at large load condition and it operates in Pulse

Width

Modulation

(PWM)

with

frequency

reduction

at

light/medium load condition.

The UTC USRB02 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 USRB02 achieves high precision CV/CC regulation

and high power efficiency. It offers comprehensive protection

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

protection, feedback loop open protection, short circuit protection,



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

* Multi-mode operation for efficiency improving

* Programmable cable drop compensation

* Built-in leading edge blanking

* Built-in primary winding inductance compensation

* Built-in line voltage compensation

* Audio noise free operation

* Open circuit protection

* Output over voltage protection

* VDD over voltage protection

* Short circuit protection

* Over temperature protection



ORDERING INFORMATION

Ordering Number

Package

Packing

USRB02G-S08-R

SOP-8

Tape Reel

USRB02G-S08-R

(1)Packing Type

(2)Package Type

(1) R: Tape Reel

(2) S08: SOP-8

(3) G: Halogen Free and Lead Free

(3)Green Package