L4941
April 1994
VERY LOW DROP 1A REGULATOR
.
LOW DROPOUT VOLTAGE (450 mV typ
at 1A)
.
VERY LOW QUIESCENT CURRENT
.
THERMAL SHUTDOWN
.
SHORT CIRCUIT PROTECTION
.
REVERSE POLARITY PROTECTION
DESCRIPTION
The L4941 is a three terminal 5 V positive regulator
available in TO-220, SOT-82, SOT-194 and DPAK
packages, making it useful in a wide range of the
industrial and consumer applications. Thanks to its
very low input/output voltage drop, this device is
particularly suitable for battery powered equipment,
reducing consumption and prolonging battery life. It
employs internal current limiting, antisaturation
circuit, thermal shut-down and safe area protection.
TO-22 0
DPA K (TO-252)
BLOCK DIAGRAM
SOT-82
SOT-194
1
3
1/13
ABSOLUTE MAXIMUM RATINGS
Symbol
Parameter
Value
Unit
V
i
Forward Input Voltage
30
V
V
i R
Reverse Input Voltage (R
O
= 100
)
15
V
I
O
Output Current
Internally Limited
P
t o t
Power Dissipation
Internally Limited
T
j
, T
s t g
Junction and Storage Temperature
40 to 150
C
PIN CONNECTIONS AND ORDERING NUMBER (top view)
THERMAL DATA
SOT-82
SOT-194
DPAK
TO-220
R
thj-case
Thermal Resistance Junction-case
Max
8
3
o
C/W
R
thj-amb
Termal resistance Junction-ambient
Max
100
50
o
C/W
TO-220
SOT-82 /SOT-194
ORDERING NUMBERS
OUTPUT VOLTAGE
PACKAGE
L4941BV
5V
TO-220
L4941BX
5V
SOT-82
L4941BS
5V
SOT-194
L4941BDT
5V
DPAK
DPAK
L4941
2/13
Figure 2 : Load Regulation.
Figure 3 : Ripple Rejection.
Figure 1 : DC Parameters.
TEST CIRCUITS
L4941
3/13
ELECTRICAL CHARACTERISTICS (refer to the test circuits T
j
= 25
C, C
i
= 0.1
F, C
o
= 22
F,
unless otherwise specified)
Symbol
Parameter
Test Conditions
Min.
Typ.
Max.
Unit
Output Voltage
5
Input Voltage (unless otherwise specified)
7
V
o
Output Voltage
I
o
= 5 mA to 1 A
V
i
= 6 V to 14 V
4.8
5
5.2
V
V
i
Operating Input Voltage
I
o
= 5 mA
16
V
V
o
Line Regulation
V
i
= 6 V to 16 V
I
o
= 5 mA
5
20
mV
V
o
Load Regulation
I
o
= 5 mA to 1 A
I
o
= 0.5 A to 1 A
8
5
20
15
mV
I
Q
Quiescent Current
I
o
= 5 mA
4
8
V
i
= 6 V
I
o
= 1 A
20
40
mA
I
Q
Quiescent Current
Change
I
o
= 5 mA
3
V
i
= 6 V to 14 V
I
o
= 1 A
10
mA
V
d
Dropout Voltage
I
o
= 0.5 A
250
450
I
o
= 1 A
450
700
mV
V
o
____
T
Output Voltage Drift
0.6
mV/
C
SVR
Supply Voltage
Rejection
f = 120 Hz
I
o
= 0.5 A
58
68
dB
I
s c
Short Circuit Current
Limit
V
i
= 14 V
1.6
2.0
V
i
= 6 V
1.8
2.2
A
Z
o
Output Impedance
f = 1 kHz
I
o
= 0.5 A
30
m
e
N
Output Noise Voltage
B = 100 Hz to 100 kHz
30
V/V
o
Figure 4 : Dropout voltage vs. Output Current.
Figure 5 : Dropout Voltage vs. Temperature.
L4941
4/13
Figure 6 : Output voltage vs. Temperature.
Figure 7 : Quiescent Current vs. Temperature
Figure 8 : Quiescent Current vs.Input Voltage.
Figure 9 : Quiescent Current vs.Output Current.
Figure 10 : Short-circuit Current vs. Temperature.
Figure 11 : Peak Output Current vs. Input/Output
Differential Voltage.
L4941
5/13
Figure 12 : Low Voltage Behavior.
Figure 13 : Supply Voltage Rejection vs.
Frequency
Figure 14 : Supply Voltage Rejection vs. Output
Current.
Figure 15 : Load Dump Characteristics.
Figure 16 : Line Transient Response.
Figure 17 : Load Transunt Response.
L4941
6/13
Figure 18 : Total Power Dissipation (TO-220).
Figure 19 : Distribued Supply with On-card L4940 and L4941 Low-drop Regulators.
ADVANTAGES OF THESE APPLICATIONS ARE :
-
On card regulation with short-circuit and thermal protection on each output.
-
Very high total system efficiency due to the switching preregulation and very low-drop postregulations.
L4941
7/13
Figure 20 : Distribued Supply with On-card L4940 and L4941 Low-drop Regulators.
L4941
8/13
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
4.8
0.189
C
1.37
0.054
D
2.4
2.8
0.094
0.110
D1
1.2
1.35
0.047
0.053
E
0.35
0.55
0.014
0.022
F
0.8
1.05
0.031
0.041
F2
1.15
1.4
0.045
0.055
G
4.95
5.08
5.21
0.195
0.200
0.205
H2
10.4
0.409
H3
10.05
10.4
0.396
0.409
L2
16.2
0.638
L3
26.3
26.7
27.1
1.035
1.051
1.067
L5
2.6
3
0.102
0.118
L6
15.1
15.8
0.594
0.622
L7
6
6.6
0.236
0.260
Dia.
3.65
3.85
0.144
0.152
TO-220 MECHANICAL DATA
P011D
L4941
9/13
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
7.4
7.8
0.291
0.307
B
10.5
11.3
0.413
0.445
b
0.7
0.9
0.028
0.035
b1
0.49
0.75
0.019
0.030
C
2.4
2.7
0.04
0.106
c1
1.2
0.047
D
15.7
0.618
e
2.2
0.087
e3
4.4
0.173
F
3.8
0.150
H
2.54
0.100
F
A
H
B
D
e3
e
b1
c1
C
b
SOT-82 MECHANICAL DATA
P032A
L4941
10/13
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
7.4
7.8
0.291
0.307
B
10.5
11.3
0.413
0.445
b
0.7
0.9
0.028
0.035
b1
0.49
0.75
0.019
0.030
C
2.4
2.7
0.094
0.106
c1
1.2
0.047
c2
1.3
0.051
D
6
0.236
e
2.2
0.087
e3
4.4
0.173
F
3.8
0.150
H
2.54
0.100
P
45
(typ.)
S
4
0.157
S1
2
0.079
T
0.1
0.004
F
A
H
B
D
e3
e
b1
c2
C
b
P
T
C1
S
S1
SOT-194 MECHANICAL DATA
P032B
L4941
11/13
DIM.
mm
inch
MIN.
TYP.
MAX.
MIN.
TYP.
MAX.
A
2.2
2.4
0.086
0.094
A1
0.9
1.1
0.035
0.043
B
0.64
0.8
0.025
0.031
B1
3.4
3.6
0.133
0.141
B2
5.2
5.4
0.204
0.212
B3
0.9
0.035
B4
1.9
2.1
0.074
0.082
C
0.48
0.6
0.018
0.023
C1
0.45
0.6
0.017
0.023
D
6
6.2
0.236
0.244
E
6.4
6.6
0.252
0.260
G
4.4
4.6
0.173
0.181
H
9.35
10.1
0.368
0.397
L
2.55
3.05
0.100
0.120
L1
0.6
1
0.023
0.039
L2
0.8
0.031
L3
0.8
1.2
0.031
0.047
L4
0.3
0.45
0.012
0.017
D
A
C
C1
L
L2
=
G
=
L1
L4
H
A1
L3
12
3
==
==
==
==
B
B3
B2
E
B1
B4
TO-252 (DPAK) MECHANICAL DATA
L4941
12/13
Information furnished is believed to be accurate and reliable. However, SGS-THOMSON Microelectronics assumes no responsability for the
consequences of use of such information nor for any infringement of patents or other rights of third parties which may results from its use. No
license is granted by implication or otherwise under any patent or patent rights of SGS-THOMSON Microelectronics. Specificationsmentioned
in this publication are subject to change without notice. This publication supersedes and r eplaces all information previously supplied.
SGS-THOMSON Microelectronics products are not authorized for use as critical componentsin life s upport devices or systems without express
written approval of SGS-THOMSON Microelectonics.
1994 SGS-THOMSON Microelectronics - All Rights Reserved
SGS-THOMSON Microelectronics GROUP OF COMPANIES
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L4941
13/13
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