Si91822

Vishay Siliconix

New Product

Document Number: 71671

S-04932—Rev. A, 15-Oct-01

www.vishay.com

1

Micropower 300-mA CMOS LDO Regulator

With Error Flag/Power-On-Reset

FEATURES

D Low 150-mV Dropout at 300-mA Load

D Guaranteed 300-mA Output Current

D 600-mA Peak Output Current Capability

D Uses Low ESR Ceramic Output Capacitor

D Fast Load and Line Transient Response

D Only 100-mV(rms) Noise With Noise Bypass

Capacitor

D 1-mA Maximum Shutdown Current

D Built-in Short Circuit and Thermal Protection

D Out-Of-Regulation Error Flag (Power Good or POR)

D Fixed1.215-V, 1.5-V, 1.8-V, 2.0-V, 2.5-V, 2.8-V, 3.0-V,

3.3-V, 5.0-V, or Adjustable Output Voltage Options

D Other Output Voltages Available by Special Order

APPLICATIONS

D Cellular Phones

D Laptop and Palm Computers

D PDA, Digital Still Cameras

DESCRIPTION

The Si91822 is a 300-mA CMOS LDO (low dropout) voltage

regulator. The device features ultra low ground current and

dropout voltage to prolong battery life in portable electronics.

The Si91822 offers line/load transient response and ripple

rejection superior to that of bipolar or BiCMOS LDO regulators.

The device is designed to maintain regulation while delivering

600-mA peak current. This is useful for systems that have high

surge current upon turn-on. The Si91822 is designed to drive

the lower cost ceramic, as well as tantalum, output capacitors.

The device is guaranteed stable from maximum load current

down to 0-mA load. In addition, an external noise bypass

LDO’s output noise for low noise applications.

The Si91822 also includes an out-of-regulation error flag.

When the output voltage is 5% below its nominal output

voltage, the error flag output goes low. If a capacitor is

connected to the device’s delay pin, the error flag output pin will

generate a delayed power-on-reset signal.

TYPICAL APPLICATIONS CIRCUITS

FIGURE 1. Fixed Output

FIGURE 2. Adjustable Output

FIGURE 3. Low Noise, Full Features Application

SD

18

DELAY

ERROR

27

GND

SENSE/ADJ

36

45

GND

2.2

mF

2.2

mF

Si91822

18

DELAY

ERROR

27

GND

SENSE/ADJ

36

45

GND

2.2

mF

2.2

mF

Si91822

18

DELAY

ERROR

27

GND

SENSE/ADJ

36

45

GND

2.2

mF

2.2

mF

Si91822

POR

ON/OFF

0.1

mF

0.1

mF

1 M

W

SD

SD