UNISONIC TECHNOLOGIES CO., LTD

P1786

LINEAR INTEGRATED CIRCUIT

www.unisonic.com.tw

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Copyright © 2007 Unisonic Technologies Co., Ltd

QW-R103-038.A

PWM CONTROL 3A

STEP-DOWN CONVERTER

DESCRIPTION

UTC P1786 consists of 3A step-down switching regulator

control which include a reference voltage source, oscillation

circuit, error amplifier, internal PMOS and etc with PWM.

UTC P1786 can provide low-ripple power, high efficiency,

and excellent transient characteristics. An enable function, an

over current protect and short circuit protect function are built

inside, so the operation frequency can be reduced from

300KHz to 30KHz when OCP or SCP happens. The PWM

control circuit can vary the duty ratio linearly from 100 down to

0%. This converter also includes an error amplifier circuit as

well as a soft-start circuit that prevents overshoot at startup.

Also, to minimum external component counts for an internal

compensation block is built in.

These ICs can work as step-down switching regulators with

the addition of an internal P-channel Power MOS, a coil,

capacitors, and a diode connected externally. They provides

such outstanding features: low current consumption. It is also

suitable for the operation via an AC adapter because this

converter accommodate an input voltage up to 23V.

FEATURES

* Input voltage: 3.6V ~ 23V

* Duty ratio: 0% to 100% PWM control

* Oscillation frequency: 300KHz typ.

* Soft-start, current limit, enable function

* Thermal shutdown function

* Built-in internal SW P-channel MOS

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*Pb-free plating product number: P1786L

ORDERING INFORMATION

Ordering Number

Normal

Lead Free Plating

Package

Packing

P1786-S08-R

P1786L-S08-R

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Tape Reel

P1786-S08-T

P1786L-S08-T

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