anyCAP
®
100 mA
Low Dropout Linear Regulator
ADP3309
Rev. C
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responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
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FEATURES
±1.2% accuracy over line and load regulations @ 25°C
Ultralow dropout voltage: 120 mV typical @ 100 mA
Requires only C
OUT
= 0.47 μF for stability
anyCAP LDOs are stable with all types of capacitors
(including MLCC)
Current and thermal limiting
Low noise
Low shutdown current: 1 μA
2.8 V to 12 V supply range
−20°C to +85°C ambient temperature range
Several fixed voltage options
Ultrasmall 5-lead SOT-23 package
Excellent line and load regulations
APPLICATIONS
Cellular telephones
Notebook, palmtop computers
Battery-powered systems
PCMCIA regulator
Bar code scanners
Camcorders, cameras
FUNCTIONAL BLOCK DIAGRAM
Q1
Q2
THERMAL
PROTECTION
DRIVER
ADP3309
g
m
CC
BANDGAP
REF
GND
R1
R2
OUTIN
ERR/N
SD
00141-001
Figure 1.
GENERAL DESCRIPTION
The ADP3309 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 LP2981, but offers
performance advantages. The ADP3309 stands out from
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 equivalent series resistance (ESR)
value, including ceramic types for space restricted applications.
The ADP3309 achieves ±1.2% accuracy at room temperature
and ±2.2% overall accuracy over temperature, line, and load
regulations. The dropout voltage of the ADP3309 is only
120 mV (typical) at 100 mA. This device also includes a current
limit and a shutdown feature. In shutdown mode, the ground
current is reduced to ~1 μA.
The ADP3309 operates with a wide input voltage range from
2.8 V to 12 V and delivers a load current in excess of 100 mA.
The ADP3309 anyCAP LDO offers a wide range of output
voltages.
+
–
+
–
ADP3309-3.3
IN
OUT
GND
ERR/NC
SD
ON
OFF
C2
0.47µF
C1
0.47µF
V
IN
V
OUT
= 3.3V
4
5
3
2
1
00141-002
Figure 2. Typical Application Circuit
