UNISONIC TECHNOLOGIES CO., LTD

UC3656

Preliminary

CMOS IC

www.unisonic.com.tw

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Copyright © 2011 Unisonic Technologies Co., Ltd

QW-R502-469.b

1MHz, 800mA SYNCHRONOUS

BUCK CONTROLLER

DESCRIPTION

The UTC UC3656 is a synchronous buck controller for a DC/DC

converter optimized for high-performance microprocessor applications.

It is configured with current mode for excellent line and load

transient response. At 1MHz operation frequency, the use of small

surface mount inductor and capacitor is enabled. The built-in

synchronous switch saves the use of an external Schottky diode and

increases efficiency.

The UTC UC3656 is a low-noise synchronous step-down DC/DC

converter that is ideally suited for systems requiring supplies from a

1-cell Li-ion battery or from a 3-cell to 4-cell NiCd, NiMH, or alkaline

battery.

The UTC UC3656 is generally applied in power supply for portable

devices and USB-based power system.

FEATURES

* High Efficiency (95%) Possible

* Input Voltage Range: 2.5V ~ 5.5V

* Schottky Diode is Saved

* Output Current: 800mA (@5V Input 3.3V Output)

* 1.0MHz Oscillation Frequency

* Internal ON/OFF

* 100% Duty Cycle Allows Low Dropout Operation

* Stand-by Current: 1μA (Max.)

ORDERING INFORMATION

Ordering Number

Package

Packing

Lead Free

Halogen Free

UC3656L-AF5-R

UC3656G-AF5-R

SOT-25

Tape Reel

MARKING