anyCAP™ 50 mA
Low Dropout Linear Regulator
a
ADP3308
FUNCTIONAL BLOCK DIAGRAM
FEATURES
؎1.2% Accuracy Over Line and Load Regulations
@ 25؇C
Ultralow Dropout Voltage: 80 mV Typical @ 50 mA
Requires Only CO = 0.47 F for Stability
anyCAP = Stable with All Types of Capacitors
(Including MLCC)
Q1
IN
OUT
ADP3308
THERMAL
PROTECTION
R1
R2
CC
ERR/NC
Q2
DRIVER
Gm
Current and Thermal Limiting
Low Noise
SD
Low Shutdown Current: 1 A
3.0 V to 12 V Supply Range
BANDGAP
REF
–20؇C to +85؇C Ambient Temperature Range
Several Fixed Voltage Options
Ultrasmall SOT-23-5 Package
Excellent Line and Load Regulations
GND
APPLICATIONS
Cellular Telephones
Notebook, Palmtop Computers
Battery Powered Systems
PCMCIA Regulator
Bar Code Scanners
Camcorders, Cameras
GENERAL DESCRIPTION
ERR/NC
4
1
The ADP3308 is a member of the ADP330x family of precision
low dropout anyCAP voltage regulators. It is pin-for-pin and
functionally compatible with National’s LP2980, but offers
performance advantages. The ADP3308 stands out from the
conventional LDOs with a novel architecture and an enhanced
process. Its patented design requires only a 0.47 µF output
capacitor for stability. This device is stable with any type of
capacitor regardless of its ESR (Equivalent Serial Resistance)
value, including ceramic types for space restricted applications.
The ADP3308 achieves ±1.2% accuracy at room temperature
and ±2.2% overall accuracy over temperature, line and load
regulations. The dropout voltage of the ADP3308 is only
80 mV (typical) at 50 mA. This device also includes a current
limit and a shutdown feature. In shutdown mode, the ground
current is reduced to ~1 µA.
ADP3308-3.3
5
V
IN
OUT
V
= +3.3V
IN
OUT
C2
0.47F
C1
0.47F
3
2
ON
OFF
SD
GND
Figure 1. Typical Application Circuit
The ADP3308 operates with a wide input voltage range from
3.0 V to 12 V and delivers a load current in excess of 100 mA.
The ADP3308 anyCAP LDO offers a wide range of output
voltages. For 100 mA version, refer to the ADP3309 data sheet.
anyCAP is a trademark of Analog Devices, Inc.
REV. A
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 of third parties
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
Fax: 781/326-8703
World Wide Web Site: http://www.analog.com
© Analog Devices, Inc., 1998