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http://www.union-ic.com Rev.05 Jan.2015

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UM1770

500mA, Micropower, VLDO Linear Regulator

UM1770Y-xx SOT89-5

UM1770DA-xx DFN6 2.0×2.0

General Description

The UM1770 series are VLDO (very low dropout) linear regulators designed for low power

maximum dropout is just 320mV at the load current of 500mA.The internal P-channel MOSFET

pass transistor requires no base current, allowing the device to draw only 250μA during normal

operation at the maximum load current of 500mA.

Other features include high output voltage accuracy, excellent transient response, under voltage

lockout, stability with ultra low ESR ceramic capacitors as small as 1μF, short-circuit and thermal

overload protection and output current limiting.

The UM1770Y-xx series are available in SOT89-5 package and the UM1770DA-xx series are

available in a low profile DFN6 2.0×2.0 package.

Applications

Features



Bluetooth/802.11 Cards



PDAs and Notebook Computers



Portable Instruments and

Battery-Powered Systems



Cellular Phones



Very Low Dropout: 320mV(max) at 500mA



Maximum Input Voltage: 6.0V



Low Noise (10Hz to 100kHz):



±2% Voltage Accuracy at 500mA



Fast Transient Response



Under Voltage Lockout



Fixed Output Voltage of UM1770Y/DA-xx:

1.0V to 4.0V with 0.1V Interval



Adjustable Output Voltage of

UM1770Y/DA-00:

1.0V to 5.0V



Output Current Limit



Stable with 1μF Output Capacitor



Short-Circuit and Thermal Overload

Protection



Low Profile SOT89-5 and DFN6 2.0×2.0

Packages