AIC2951/2951D
Low Dropout Linear Regulator
Analog Integrations Corporation
4F, 9, Industry E. 9th Rd, Science Based Industrial Park, Hsinchu Taiwan, ROC
www.analog.com.tw
DS-2951-01 Mar 13, 00
TEL: 886-3-5772500 FAX: 886-3-5772510
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FEATURES
l
Low Dropout Voltage of 130mV at 100mA Output
Current (AIC2951/2951D-50).
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Guaranteed 150mA /300mA Output Current.
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Internal 1.3
P-MOSFET Draws no Base Current.
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Low Ground Current at 55
A.
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1% Accuracy Output of 3V/3.3V/5V.
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Error Flag Warns of Output Dropout.
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1
A Supply Current in Shutdown Mode.
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Output Programmable from 1.235V~11V.
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Fast Transient Response.
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Needs only 1
F for Stability.
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Current and Thermal Limiting.
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APPLICATIONS
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Voltage Regulator for Pentium
CPUs.
l
Wireless Communication System.
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Battery Powered Systems.
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DESCRIPTION
The AIC2951/ 2951D series is the enhanced
CMOS version of the LP2951. The superior char-
acteristics of the AIC2951/ 2951D series include
zero base current loss, very low dropout voltage,
and 1% accuracy output voltage. Typical ground
current remains approximately 55
A, from no
load to maximum loading conditions. Dropout
voltage at 100mA output current is significantly
lower than its bipolar counterpart: 130mV for the
AIC2951-50/2951D-50, 180mV for the AIC2951-
33/ 2951D-33, and 200mV for the AIC2951-30/
2951D-30. Output current limiting and thermal
limiting are built in to provide maximal protection
to the AIC2951/2951D series from fault condi-
tions.
An error flag output, indicating when output volt-
age drops out of regulation, often due to the
falling batteries on the input, can be used for a
power-on reset. A logic-controlled shutdown
input enables the regulator to be switched on and
off. The part may be configured for a fixed output
voltage or programmed from 1.235V to 11V with
an external pair of resistors. The part comes in 8-
pin DIP or SO packages.
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TYPICAL APPLICATION CIRCUIT
ERROR
C2
R2
R1
R3
390
R4
33
Q1
D45H2A
AIC2951
8
7
6
5
4
3
2
1
FB
GND
SENSE
SHDN
TAP
VIN
VOUT
V
IN
470
F
V
OUT
1000
F
V
OUT
=1.235(1+R1/R2)
+
C1
+
Pentium Processor Power Supply
AIC2951/2951D
Low Dropout Linear Regulator
2
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ORDERING INFORMATION
AIC2951 X-XXXX
ORDER NUMBER
AIC2951-30CN
AIC2951-33CN
AIC2951-50CN
AIC2951D-30CN
AIC2951D-33CN
AIC2951D-50CN
(PLASTIC DIP)
AIC2951-30CS
AIC2951-33CS
AIC2951-50CS
AIC2951D-30CS
AIC2951D-33CS
AIC2951D-50CS
(PLASTIC SO)
PIN CONFIGURATION
TOP VIEW
TAP
1
3
4
2
8
6
5
7
VIN
SENSE
SHDN
GND
FB
ERROR
VOUT
PACKAGE TYPE
N: PLASTIC DIP
S: SMALL OUTLINE
TEMPERATURE RANGE
C: 0
C~+70
C
OUTPUT VOLTAGE
30 : 3.0V
33 :
3.3V
50 :
5.0V
MAX. OUTPUT CURRENT
DEFAULT
: 150mA
D : 300mA
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ABSOLUTE MAXIMUM RATINGS
Input Supply Voltage ........................... ... ... ... ... ............................................... -0.3~12V
Feedback Input Voltage..................................... ... ... ... ... .................................. -0.3~12V
Shutdown Input Voltage ................................... ... ... ... ... .................................. -0.3~12V
Error Comparator Output ......................................... ... ... ... .............................. -0.3~12V
Operating Junction Temperature Range ................ ... ... ... .......................... -40
C~125
C
Storage Temperature Range ............................... ... ... ... ............................ -65
C~150
C
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TEST CIRCUIT
ERROR
C
IN
1
F
1mA
+
+
C
OUT
10
F
SHUTDOWN
AIC2951
VIN
FB
TAP
GND
SHDN
SENSE
VOUT
V
OUT
V
REF
V
IN
AIC2951/2951D
3
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ELECTRICAL CHARACTERISTICS
(Ta=25
C, C
IN
=1
F, C
OUT
=10
F, unless oth-
erwise specified.)
PARAMETER
TEST CONDITIONS
MIN.
TYP. MAX.
UNIT
Output Voltage
No Load
AIC2951/2951D-50
AIC2951/2951D-33
AIC2951/2951D-30
V
IN
=5.5~12V
V
IN
=3.6~12V
V
IN
=3.3~12V
4.950
3.267
2.970
5.0
3.3
3.0
5.050
3.333
3.030
V
Output Voltage Tempera-
ture Coefficiency
(Note 1)
50
150
PPM/
C
Line Regulation
I
L
=1mA
AIC2951/2951D-50
AIC2951/2951D-33
AIC2951/2951D-30
V
IN
=5.5~12V
V
IN
=3.6~12V
V
IN
=3.3~12V
3
3
3
10
10
10
mV
Load Regulation
(Note 2)
AIC2951-50
AIC2951D-50
AIC2951-30/ -33
AIC2951D-30/-33
V
IN
=7V, I
L
=0.1~150mA
V
IN
=7V, I
L
=0.1~300mA
V
IN
=5V, I
L
=0.1~150mA
V
IN
=5V, I
L
=0.1~300mA
7
7
7
7
15
25
15
25
mV
Current Limit
(Note 3)
AIC2951-50
AIC2951-30/ -33
AIC2951D-50
AIC2951D-30/ -33
V
IN
=7V, V
OUT
=0V
V
IN
=5V, V
OUT
=0V
V
IN
=7V, V
OUT
=0V
V
IN
=5V, V
OUT
=0V
220
220
440
440
MA
Dropout Voltage
(Note 4)
AIC2951/2951D
AIC2951-50
AIC2951-33
AIC2951-30
AIC2951D-50
AIC2951D-33
AIC2951D-30
I
L
=0.1mA
I
L
=150mA
I
L
=150mA
I
L
=150mA
I
L
=300mA
I
L
=300mA
I
L
=300mA
0.2
200
270
300
400
540
600
10
300
370
400
500
640
700
mV
Ground Current
I
O
=0.1mA~I
MAX
AIC2951/2951D-50
AIC2951/2951D-33
AIC2951/2951D-30
V
IN
=5.5~12V
V
IN
=4~12V
V
IN
=4~12V
55
55
55
80
80
80
A
FB Reference Voltage
AIC2951-50
AIC2951-30/ -33
V
IN
=5.5~12V
V
IN
=3.6~12V
1.222
1.222
1.235
1.235
1.248
1.248
V
Reference Voltage Temp.
Coef.
(Note 1)
50
150
PPM/
C
FB Pin Current
AIC2951/2951D
V
IN
=7V
20
60
NA
Error Pin off Leakage
Current
AIC2951/2951D
V
IN
=7V
1
A
Error Pin Pull Low
Voltage
I
OL
=1mA
AIC2951/2951D-50
AIC2951/2951D-33
V
IN
=4.5V
V
IN
=2.9V
100
100
300
300
mV
AIC2951/2951D
4
AIC2951/2951D-30
V
IN
=2.7V
100
300
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ELECTRICAL CHARACTERISTICS
(CONTINUED)
PARAMETER
TEST CONDITIONS
MIN.
TYP. MAX.
UNIT
Output Voltage
No Load
AIC2951/2951D-50
AIC2951/2951D-33
AIC2951/2951D-30
V
IN
=5.5~12V
V
IN
=3.6~12V
V
IN
=3.3~12V
4.950
3.267
2.970
5.0
3.3
3.0
5.050
3.333
3.030
V
Error Pin Upper Thresh-
old Voltage
40
60
mV
Error Pin Lower Threshold
Voltage
68
88
MV
Shutdown Threshold
Voltage
AIC2951/2951D
V
IN
=7V
0.5
0.8
2
V
Shutdown Input Bias
Current
AIC2951/2951D
V
IN
=7V, V
SHDN
=2V
10
25
A
Shutdown Supply
Current
AIC2951/2951D
V
IN
=7V, V
SHDN
=2V
2
A
Note 1:
Guaranteed by design.
Note 2:
Regulation is measured at constant junction temperature, using pulse testing with a low ON time.
Note 3:
Current limit is measured by pulsing a short time.
Note 4:
Dropout voltage is defined as the input to output differential at which the output voltage drops 100mV
below the value measured with a 1V differential.
AIC2951/2951D
5
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TYPICAL PERFORMANCE CHARACTERISTICS
Reference Voltage vs Temperature
Reference Voltage (V)
Temperature(
C)
0
25
50
75
100
125
-25
-50
V
REF
=1.244V
V
REF
=1.235V
V
REF
=1.225V
1.18
1.2
1.22
1.24
1.26
1.28
Ground Current vs. Input Voltage
Ground Current (
A)
Input Voltage (V)
0
1
2
3
4
5
6
7
8
0
10
20
30
40
50
60
Ground Current vs. Temperature
Ground Current (
A)
Temperature(
C)
125
0
25
50
75
100
-25
-50
50
52
54
56
58
60
I
L
=300mA
I
L
=150mA
I
L
=0.1mA
Dropout Voltage vs Load Current
Dropout Voltage (mV)
Load Current (mA)
600
V
OUT
=3V
0
50
100
150
200
250
300
0
100
200
300
400
500
V
OUT
=3.3V
V
OUT
=5V
Temperature(
C)
Dropout Voltage vs Temperature
Dropout Voltage(mV)
0
25
50
75
100
125
-25
-50
0
100
200
300
400
500
600
I
L
=300mA
I
L
=150mA
I
L
=0.1mA
V
OUT
=5V
Temperature (
C)
Short Circuit Current vs. Temperature
Short Circuit Current (mA)
0
25
50
75
100
125
-25
-50
200
300
400
500
AIC2951D
AIC2951
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