UNISONIC TECHNOLOGIES CO., LTD
LM2940
1A LOW-DROPOUT POSITIVE
VOLTAGE REGULATOR
DESCRIPTION
The UTC
LM2940
is a low dropout regulator designed to provide
output current up to 1A with a typically 500mV dropout Voltage and
a maximum of 1V. It is capable of reducing the ground current when
the differential between the input voltage and the output voltage
outrun 3V.
UTC LM2940 offers low quiescent current (typically 30mA at 1A
and an input-output differential of 5V). Higher quiescent currents
only exist when the regulator is in the dropout mode (V
IN
-V
OUT
≤3V).
LINEAR INTEGRATED CIRCUIT
1
FEATURES
* 500mV typically dropout at 1A
* Output current in excess of 1A
* Low quiescent current
* Reversed-battery protection
* Current limit and thermal shutdown.
* Mirror image insertion protection
*Pb-free plating product number: LM2940L
ORDERING INFORMATION
Order Number
Normal
Lead Free Plating
LM2940-xx-AA3- R
LM2940L-xx-AA3-R
LM2940-xx-TA3-T
LM2940L-xx-TA3-T
LM2940-xx-TN3-R
LM2940L-xx-TN3-R
LM2940-xx-TN3-T
LM2940L-xx-TN3-T
LM2940-xx-TQ2-R
LM2940L-xx-TQ2-R
LM2940-xx-TQ2-T
LM2940L-xx-TQ2-T
LM2940-xx-TQ3-R
LM2940L-xx-TQ3-R
LM2940-xx-TQ3-T
LM2940L-xx-TQ3-T
Note: 1.xx: output voltage, refer to Marking Information.
2.Pin Assignment: I: V
IN
G: GND O:V
OUT
Package
SOT-223
TO-220
TO-252
TO-252
TO-263
TO-263
TO-263-3
TO-263-3
Pin Assignment
1
2
3
I
G
O
I
G
O
I
G
O
I
G
O
I
G
O
I
G
O
I
G
O
I
G
O
Packing
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QW-R102-016.G
LM2940
MARKING INFORMATION
PACKAGE
VOLTAGE CODE
LINEAR INTEGRATED CIRCUIT
MARKING
SOT-223
TO-220
TO-252
TO-263
TO-263-3
25 :2.5V
33 :3.3V
50 : 5V
60 : 6V
80 : 8V
90 : 9V
10 :10V
12 :12V
15 :15V
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QW-R102-016.G
LM2940
ABSOLUTE MAXIMUM RATINGS
PARAMETER
LINEAR INTEGRATED CIRCUIT
RATINGS
UNIT
Input Voltage
26
V
Power Dissipation
Internally limited
Junction Temperature
+150
°C
TO-220/TO-263-3/TO-263
-40 ~ +125
°C
Operating Temperature
T
OPR
SOT-223
-40 ~ +85
°C
Storage Temperature
T
STG
-65 ~ +150
°C
Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
SYMBOL
V
IN
P
D
T
J
ELECTRICAL CHARACTERISTICS
(T
a
=T
J
=25°C, V
IN
=V
OUT
+5V, I
OUT
=1A and C
OUT
=22µF, unless otherwise specified.)
For LM2940-2.5V
PARAMETER
Output Voltage
Line Regulation
Load Regulation
Output Impedance
Quiescent Current
Output Noise Voltage
Ripple Rejection
Long Term Stability
Dropout Voltage
Short Circuit Current
Maximum Line Transient
Reverse Polarity DC Input Voltage
Reverse Polarity Transient Input
Voltage
V
D
I
SC
T
IN
V
RIN
V
TRRI
I
OUT
=1A
I
OUT
=100mA
(Note)
R
OUT
=100Ω, T
≤
100ms
R
OUT
=100Ω
R
OUT
=100Ω, T
≤
100ms
SYMBOL
V
OUT
△V
OUT
△V
OUT
R
OUT
I
Q
eN
RR
TEST CONDITIONS
6.25V
≤
V
IN
≤
26V, 5mA
≤
I
OUT
≤
1A
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
50mA
≤
I
OUT
≤
1A
100 mA DC and 20mArms, fo=120Hz
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
10Hz-100kHz, I
OUT
=5mA
fo=120Hz, 1Vrms, I
OUT
=100mA
MIN
2.425
TYP
2.5
20
20
20
10
75
64
10
0.5
0.13
2.5
75
-30
-75
0.8
0.15
MAX
2.575
25
25
15
UNIT
V
mV
mV
mΩ
mA
µVrms
dB
mV/
1000Hr
V
A
V
V
V
52
60
-15
-50
For LM2940-3.3V
PARAMETER
Output Voltage
Line Regulation
Load Regulation
Output Impedance
Quiescent Current
Output Noise Voltage
Ripple Rejection
Long Term Stability
Dropout Voltage
Short Circuit Current
Maximum Line Transient
Reverse Polarity DC Input Voltage
Reverse Polarity Transient Input
Voltage
V
D
I
SC
T
IN
V
RIN
V
TRRI
I
OUT
=1A
I
OUT
=100mA
(Note)
R
OUT
=100Ω, T
≤
100ms
R
OUT
=100Ω
R
OUT
=100Ω, T
≤
100ms
SYMBOL
V
OUT
△V
OUT
△V
OUT
R
OUT
I
Q
eN
RR
TEST CONDITIONS
6.25V
≤
V
IN
≤
26V, 5mA
≤
I
OUT
≤
1A
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
50mA
≤
I
OUT
≤
1A
100 mA DC and 20mArms, fo=120Hz
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
10Hz-100kHz, I
OUT
=5mA
fo=120Hz, 1Vrms, I
OUT
=100mA
MIN
3.2
TYP
3.3
20
25
25
10
99
64
14
0.5
0.13
2.5
75
-30
-75
0.8
0.15
MAX
3.4
33
33
15
UNIT
V
mV
mV
mΩ
mA
µVrms
dB
mV/
1000Hr
V
A
V
V
V
52
60
-15
-50
UNISONIC TECHNOLOGIES CO., LTD
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3 of 13
QW-R102-016.G
LM2940
ELECTRICAL CHARACTERISTICS(Cont.)
For LM2940-5.0V
PARAMETER
Output Voltage
Line Regulation
Load Regulation
Output Impedance
Quiescent Current
Output Noise Voltage
Ripple Rejection
Long Term Stability
Dropout Voltage
Short Circuit Current
Maximum Line Transient
Reverse Polarity DC Input Voltage
Reverse Polarity Transient Input
Voltage
V
D
I
SC
T
IN
V
RIN
V
TRRI
SYMBOL
V
OUT
△V
OUT
△V
OUT
R
OUT
I
Q
eN
RR
LINEAR INTEGRATED CIRCUIT
TEST CONDITIONS
6.25V
≤
V
IN
≤
26V, 5mA
≤
I
OUT
≤
1A
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
50mA
≤
I
OUT
≤
1A
100 mA DC and 20mArms, fo=120Hz
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
10Hz-100kHz, I
OUT
=5mA
fo=120Hz, 1Vrms, I
OUT
=100mA
MIN
4.85
54
TYP
5.00
20
35
35
10
150
72
20
MAX
5.15
50
50
15
UNIT
V
mV
mV
mΩ
mA
µVrms
dB
mV/
1000Hr
V
A
V
V
V
I
OUT
=1A
I
OUT
=100mA
(Note)
R
OUT
=100Ω, T
≤
100ms
R
OUT
=100Ω
R
OUT
=100Ω, T
≤
100ms
60
-15
-50
0.5
0.13
2.5
75
-30
-75
0.8
0.15
For LM2940-6.0V
PARAMETER
Output Voltage
Line Regulation
Load Regulation
Output Impedance
Quiescent Current
Output Noise Voltage
Ripple Rejection
Long Term Stability
Dropout Voltage
Short Circuit Current
Maximum Line Transient
Reverse Polarity DC Input Voltage
Reverse Polarity Transient Input
Voltage
V
D
I
SC
T
IN
V
RIN
V
TRRI
I
OUT
=1A
I
OUT
=100mA
(Note)
R
OUT
=100Ω, T
≤
100ms
R
OUT
=100Ω
R
OUT
=100Ω, T
≤
100ms
SYMBOL
V
OUT
△V
OUT
△V
OUT
R
OUT
I
Q
eN
RR
TEST CONDITIONS
7.5V
≤
V
IN
≤
26V, 5mA
≤
I
OUT
≤
1A
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
50mA
≤
I
OUT
≤
1A
100 mA DC and 20mArms, fo=120Hz
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
10Hz-100kHz, I
OUT
=5mA
fo=120Hz, 1Vrms, I
OUT
=100mA
MIN
5.82
TYP
6.00
20
40
40
10
180
72
20
0.5
0.13
2.5
75
-30
-75
0.8
0.15
MAX
6.18
60
60
15
UNIT
V
mV
mV
mΩ
mA
µVrms
dB
mV/
1000Hr
V
A
V
V
V
60
60
-15
-50
UNISONIC TECHNOLOGIES CO., LTD
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4 of 13
QW-R102-016.G
LM2940
ELECTRICAL CHARACTERISTICS(Cont.)
For LM2940-8.0V
PARAMETER
Output Voltage
Line regulation
Load Regulation
Output Impedance
Quiescent Current
Output Noise Voltage
Ripple Rejection
Long Term Stability
Dropout Voltage
Short Circuit Current
Maximum Line Transient
Reverse Polarity DC Input Voltage
Reverse Polarity Transient Input
Voltage
V
D
I
SC
T
IN
V
RIN
V
TRRI
SYMBOL
V
OUT
△V
OUT
△V
OUT
R
OUT
I
Q
eN
RR
LINEAR INTEGRATED CIRCUIT
TEST CONDITIONS
9.4V
≤
V
IN
≤
26V, 5mA
≤
I
OUT
≤
1A
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
50mA
≤
I
OUT
≤1A
100 mA DC and 20mArms, fo=120Hz
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
10Hz-100kHz, I
OUT
=5mA
fo=120Hz, 1Vrms, I
OUT
=100mA
MIN
7.76
54
TYP
8.00
20
55
55
10
240
66
32
MAX
8.24
80
80
15
UNIT
V
mV
mV
mΩ
mA
µVrms
dB
mV/
1000Hr
V
A
V
V
V
I
OUT
=1A
I
OUT
=100mA
(Note)
R
OUT
=100Ω, T
≤
100ms
R
OUT
=100Ω
R
OUT
=100Ω, T
≤
100ms
60
-15
-50
0.5
0.13
2.5
75
-30
-75
0.8
0.15
For LM2940-9.0V
PARAMETER
Output Voltage
Line regulation
Load Regulation
Output Impedance
Quiescent Current
Output Noise Voltage
Ripple Rejection
Long Term Stability
Dropout Voltage
Short Circuit Current
Maximum Line Transient
Reverse Polarity DC Input Voltage
Reverse Polarity Transient Input
Voltage
V
D
I
SC
T
IN
V
RIN
V
TRRI
I
OUT
=1A
I
OUT
=100mA
(Note)
R
OUT
=100Ω, T
≤
100ms
R
OUT
=100Ω
R
OUT
=100Ω, T
≤
100ms
SYMBOL
V
OUT
△V
OUT
△V
OUT
R
OUT
I
Q
eN
RR
TEST CONDITIONS
10.5V
≤
V
IN
≤
26V, 5mA
≤
I
OUT
≤
1A
V
OUT
+2V
≤
V
IN
≤
26V, I
OUT
=5mA
50mA
≤
I
OUT
≤
1A
100 mA DC and 20mArms, fo=120Hz
V
OUT
+2V
≤
VIN
≤
26V, I
OUT
=5mA
10Hz-100kHz, I
OUT
=5mA
fo=120Hz, 1Vrms, I
OUT
=100mA
MIN
8.73
TYP
9.00
20
60
60
10
270
64
34
0.5
0.13
2.5
75
-30
-75
0.8
0.15
MAX
9.27
90
90
15
UNIT
V
mV
mV
mΩ
mA
µVrms
dB
mV/
1000Hr
V
A
V
V
V
52
60
-15
-50
UNISONIC TECHNOLOGIES CO., LTD
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5 of 13
QW-R102-016.G
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