UNISONIC TECHNOLOGIES CO., LTD

UPSR104

Preliminary

CMOS IC

www.unisonic.com.tw

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Copyright © 2016 Unisonic Technologies Co., Ltd

QW-R103-113.a

HIGH PRECISION CC/CV

PRIMARY-SIDE PWM

CONTROLLER



DESCRIPTION

The UTC UPSR104 is a primary controller 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 UPSR104 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 UPSR104 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, VDD over voltage protection, VDD clamp, OTP,

leading edge blanking, VDD under voltage lockout, etc.

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FEATURES

SOT-26

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* ±5% Constant Voltage Regulation at Universal AC input

* High Precision Constant Current Regulation at Universal AC input

* Primary-side Sensing and Regulation Without TL431 and

Opto-coupler

* Programmable CV and CC Regulation

* Adjustable Constant Current and Output Power Setting

* Built-in Secondary Constant Current Control with Primary Side

Feedback

* Built-in Adaptive Current Peak Regulation

* Built-in Primary winding inductance

compensation

* Programmable Cable drop Compensation

* Power on Soft-start

* Built-in Leading Edge Blanking (LEB)

* Cycle-by-Cycle Current Limiting

(UVLO)

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ORDERING INFORMATION

Ordering Number

Package

Packing

UPSR104G-AG6-R

SOT-26

Tape Reel