150 mA, Low Quiescent Current,
CMOS Linear Regulator
Data Sheet
ADP121
FEATURES
TYPICAL APPLICATION CIRCUITS
Input voltage range: 2.3 V to 5.5 V
Output voltage range: 1.2 V to 3.3 V
Output current: 150 mA
V
= 2.3V
V
= 1.8V
OUT
IN
1
2
3
VIN
GND
EN
VOUT
5
C
C
IN
1µF
OUT
1µF
Low quiescent current
I
I
GND = 11 μA with 0 ꢀA load
GND = 30 μA with 150 mA load
4
NC
ON
OFF
NC = NO CONNECT
Low shutdown current: <1 μA
Low dropout voltage
Figure 1. ADP121 TSOT with Fixed Output Voltage, 1.8 V
90 mV @ 150 mA load
High PSRR
V
= 1.8V
V
= 2.3V
OUT
70 dB @ 1 kHz at VOUT = 1.2 V
70 dB @ 10 kHz at VOUT = 1.2 V
Low noise: 40 μV rms at VOUT = 1.2 V
No noise bypass capacitor required
Output voltage accuracy: 1ꢁ
Stable with a small 1 μF ceramic output capacitor
Current limit and thermal overload protection
Logic controlled enable
IN
VIN
VOUT
C
C
IN
OUT
1µF
1µF
ON
EN
GND
OFF
Figure 2. ADP121 WLCSP with Fixed Output Voltage, 1.8 V
5-lead TSOT package
4-ball 0.4 mm pitch WLCSP
APPLICATIONS
Mobile phones
Digital cameras and audio devices
Portable and battery-powered equipment
Post dc-to-dc regulation
Post regulation
GENERAL DESCRIPTION
The ADP121 is a quiescent current, low dropout, linear regulator
that operates from 2.3 V to 5.5 V and provides up to 150 mA of
output current. The low 135 mV dropout voltage at 150 mA
load improves efficiency and allows operation over a wide
input voltage range. The low 30 μA of quiescent current at full
load makes the ADP121 ideal for battery-operated portable
equipment.
The ADP121 is available in output voltages ranging from 1.2 V
to 3.3 V. The parts are optimized for stable operation with small
1 ꢀF ceramic output capacitors. The ADP121 delivers good
transient performance with minimal board area.
Short-circuit protection and thermal overload protection circuits
prevent damage in adverse conditions. The ADP121 is available
in a tiny 5-lead TSOT and 4-ball 0.4 mm pitch halide-free
WLCSP packages and utilizes the smallest footprint solution to
meet a variety of portable applications.
Rev. G
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights ofthird parties that may result fromits use. Specifications subject to change without notice. No
licenseis granted byimplication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registeredtrademarks arethe property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781.329.4700
www.analog.com
Fax: 781.461.3113 ©2008–2012 Analog Devices, Inc. All rights reserved.