UNISONIC TECHNOLOGIES CO., LTD

US251

Preliminary

CMOS IC

www.unisonic.com.tw

1 of 5

Copyright © 2015 Unisonic Technologies Co., Ltd

QW-R129-008.a

CURRENT-LIMITED,

POWER-DISTRIBUTION

SWITCHES



DESCRIPTION

The UTC US251 is a power distribution switch. It is intended for

applications such as USB where heavy capacitive loads and

short-circuits are likely to be encountered. This family offers

multiple devices with fixed current-limit thresholds for applications

between 0.5A and 2A.

open-drain output report over-current or over-temperature event

which has deglitch typical 9ms timeout period typically 9ms.

The UTC US251 incorporates protection circuits including

current limiting circuit with foldback function, thermal shutdown

circuit designed to prevent catastrophic switch failure due to

increasing power dissipation when continuous heavy loads or short

circuit occurs. Besides, a built-in charge pump is used to drive the

N-channel MOSFET that is free of parasitic body diode to eliminate

any reversed current flow across the switch when it is powered off.

The UTC US251 is applied in high-side power protection switch,

USB power management, USB host and self-powered bubs, USB

bus-powered hubs, hot plug-in power supplies, battery-charger

circuits.



FEATURES

* Single Power Switch Family

* 80-mΩ High-Side MOSFET

* Rated currents of 0.5 A, 1 A, 1.5 A, 2 A

* Accurate, Fixed, Constant Current Limit

* Deglitched Fault Reporting

* Output Discharge When Disabled

* Reverse Current Blocking

* Built-in Softstart



ORDERING INFORMATION

Ordering Number

Package

Packing

US251G-xx-AF5-R

SOT-25

Tape Reel

(1) R: Tape Reel

(2) AF5: SOT-25

(3) 08: 0.8mA, 16: 1.6mA, 22: 2.2mA, 29: 2.9mA

(4) G: Halogen Free and Lead Free

US251G-xx-AF5-R

(1)Packing Type

(2)Package Type

(3)Current Limit

(4)Green Package