S-T111 Series

www.sii-ic.com

HIGH RIPPLE-REJECTION

LOW DROPOUT CMOS VOLTAGE REGULATOR

© Seiko Instruments Inc., 2003-2015

Seiko Instruments Inc.

1

The S-T111 Series is a positive voltage regulator with a low dropout voltage, high-accuracy output voltage, and

low current consumption developed based on CMOS technology.

A built-in low on-resistance transistor provides a low dropout voltage and large output current, and a built-in

overcurrent protection circuit prevents the load current from exceeding the current capacity of the output

transistor. An ON/OFF circuit ensures a long battery life. Compared with the voltage regulators using the

conventional CMOS technology, a larger variety of capacitors are available, including small ceramic capacitors.

A small SOT-23-5 package realizes high-density mounting.



Features

• Output voltage:

1.5 V to 5.5 V, selectable in 0.1 V step

• Output voltage accuracy:

±1.0%

• Dropout voltage:

• Current consumption:

During operation: 50

μA typ., 90 μA max.

During power-off: 0.1

μA typ., 1.0 μA max.

• Output current:

*1

• Input and output capacitors:

A ceramic capacitor of 0.1

μF or more can be used.

• Ripple rejection:

80 dB typ. (f = 1.0 kHz)

• Built-in overcurrent protection circuit:

Limits overcurrent of output transistor.

• Built-in ON/OFF circuit:

Ensures long battery life.

• Operation temperature range:

Ta =

−40°C to +85°C

• Lead-free, Sn 100%, halogen-free

*2

*1. Attention should be paid to the power dissipation of the package when the output current is large.

*2. Refer to “ Product Name Structure” for details.



Applications

• Constant-voltage power supply for battery-powered device

• Constant-voltage power supply for personal communication device

• Constant-voltage power supply for home electric/electronic appliance

• Constant-voltage power supply for cellular phone



Package

• SOT-23-5