LM723/LM723C Voltage Regulator
LM723/LM723C
Voltage Regulator
General Description
The LM723/LM723C is a voltage regulator designed prima-
rily for series regulator applications. By itself, it will supply
output currents up to 150 mA; but external transistors can be
added to provide any desired load current. The circuit fea-
tures extremely low standby current drain, and provision is
made for either linear or foldback current limiting.
The LM723/LM723C is also useful in a wide range of other
applications such as a shunt regulator, a current regulator or
a temperature controller.
The LM723C is identical to the LM723 except that the
LM723C has its performance guaranteed over a 0C to
+70C temperature range, instead of -55C to +125C.
Features
n
150 mA output current without external pass transistor
n
Output currents in excess of 10A possible by adding
external transistors
n
Input voltage 40V max
n
Output voltage adjustable from 2V to 37V
n
Can be used as either a linear or a switching regulator
Connection Diagrams
Dual-In-Line Package
DS008563-2
Top View
Order Number LM723J/883 or LM723CN
See NS Package J14A or N14A
Metal Can Package
DS008563-3
Note: Pin 5 connected to case.
Top View
Order Number LM723H, LM723H/883 or LM723CH
See NS Package H10C
June 1999
LM723/LM723C
V
oltage
Regulator
1999 National Semiconductor Corporation
DS008563
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Connection Diagrams
(Continued)
Equivalent Circuit
*
Typical Application
DS008563-20
Top View
Order Number LM723E/883
See NS Package E20A
DS008563-4
*Pin numbers refer to metal can package.
DS008563-8
for minimum temperature drift.
Typical Performance
Regulated Output Voltage
5V
Line Regulation (
V
IN
= 3V)
0.5mV
Load Regulation (
I
L
= 50 mA)
1.5mV
FIGURE 1. Basic Low Voltage Regulator
(V
OUT
= 2 to 7 Volts)
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2
Absolute Maximum Ratings
(Note 1)
If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
(Note 10)
Pulse Voltage from V
+
to V
-
(50 ms)
50V
Continuous Voltage from V
+
to V
-
40V
Input-Output Voltage Differential
40V
Maximum Amplifier Input Voltage
(Either Input)
8.5V
Maximum Amplifier Input Voltage
(Differential)
5V
Current from V
Z
25 mA
Current from V
REF
15 mA
Internal Power Dissipation
Metal Can (Note 2)
800 mW
Cavity DIP (Note 2)
900 mW
Molded DIP (Note 2)
660 mW
Operating Temperature Range
LM723
-55C to +150C
LM723C
0C to +70C
Storage Temperature Range
Metal Can
-65C to +150C
Molded DIP
-55C to +150C
Lead Temperature (Soldering, 4 sec. max.)
Hermetic Package
300C
Plastic Package
260C
ESD Tolerance
1200V
(Human body model, 1.5 k
in series with 100 pF)
Electrical Characteristics
(Note 3) (Note 10)
Parameter
Conditions
LM723
LM723C
Units
Min
Typ
Max
Min
Typ
Max
Line Regulation
V
IN
= 12V to V
IN
= 15V
0.01
0.1
0.01
0.1
% V
OUT
-55C
T
A
+125C
0.3
% V
OUT
0C
T
A
+70C
0.3
% V
OUT
V
IN
= 12V to V
IN
= 40V
0.02
0.2
0.1
0.5
% V
OUT
Load Regulation
I
L
= 1 mA to I
L
= 50 mA
0.03
0.15
0.03
0.2
% V
OUT
-55C
T
A
+125C
0.6
% V
OUT
0C
T
A
+70C
0.6
% V
OUT
Ripple Rejection
f = 50 Hz to 10 kHz, C
REF
= 0
74
74
dB
f = 50 Hz to 10 kHz, C
REF
= 5 F
86
86
dB
Average Temperature Coeffic-
-55C
T
A
+125C
0.002 0.015
%/C
ient of Output Voltage (Note 8)
0C
T
A
+70C
0.003 0.015
%/C
Short Circuit Current Limit
R
SC
= 10
, V
OUT
= 0
65
65
mA
Reference Voltage
6.95 7.15
7.35 6.80 7.15
7.50
V
Output Noise Voltage
BW = 100 Hz to 10 kHz, C
REF
= 0
86
86
Vrms
BW = 100 Hz to 10 kHz, C
REF
= 5 F
2.5
2.5
Vrms
Long Term Stability
0.05
0.05
%/1000 hrs
Standby Current Drain
I
L
= 0, V
IN
= 30V
1.7
3.5
1.7
4.0
mA
Input Voltage Range
9.5
40
9.5
40
V
Output Voltage Range
2.0
37
2.0
37
V
Input-Output Voltage Differential
3.0
38
3.0
38
V
JA
Molded DIP
105
C/W
JA
Cavity DIP
150
C/W
JA
H10C Board Mount in Still Air
165
165
C/W
JA
H10C Board Mount in 400 LF/Min Air Flow
66
66
C/W
JC
22
22
C/W
Note 1: "Absolute Maximum Ratings" indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is
functional, but do not guarantee specific performance limits.
Note 2: See derating curves for maximum power rating above 25C.
Note 3: Unless otherwise specified, T
A
= 25C, V
IN
= V
+
= V
C
= 12V, V
-
= 0, V
OUT
= 5V, I
L
= 1 mA, R
SC
= 0, C
1
= 100 pF, C
REF
= 0 and divider impedance as
seen by error amplifier
10 k
connected as shown in
Figure 1. Line and load regulation specifications are given for the condition of constant chip temperature. Tem-
perature drifts must be taken into account separately for high dissipation conditions.
Note 4: L
1
is 40 turns of No. 20 enameled copper wire wound on Ferroxcube P36/22-3B7 pot core or equivalent with 0.009 in. air gap.
Note 5: Figures in parentheses may be used if R1/R2 divider is placed on opposite input of error amp.
Note 6: Replace R1/R2 in figures with divider shown in
Figure 13.
Note 7: V
+
and V
CC
must be connected to a +3V or greater supply.
Note 8: For metal can applications where V
Z
is required, an external 6.2V zener diode should be connected in series with V
OUT
.
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3
Electrical Characteristics
(Note 3) (Note 10) (Continued)
Note 9: Guaranteed by correlation to other tests.
Note 10: A military RETS specification is available on request. At the time of printing, the LM723 RETS specification complied with the Min and Max limits in this
table. The LM723E, H, and J may also be procured as a Standard Military Drawing.
Typical Performance Characteristics
Load Regulation
Characteristics with
Current Limiting
DS008563-22
Load Regulation
Characteristics with
Current Limiting
DS008563-23
Load & Line Regulation vs
Input-Output Voltage
Differential
DS008563-24
Current Limiting
Characteristics
DS008563-25
Current Limiting
Characteristics vs
Junction Temperature
DS008563-26
Standby Current Drain vs
Input Voltage
DS008563-27
Line Transient Response
DS008563-28
Load Transient Response
DS008563-29
Output Impedence vs
Frequency
DS008563-30
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4
Maximum Power Ratings
TABLE 1. Resistor Values (k
) for Standard Output Voltage
Positive
Applicable
Fixed
Output
Negative
Fixed
5% Output
Output
Figures
Output
Adjustable
Output
Applicable
Output
Adjustable
Voltage
5%
10% (Note 6)
Voltage
Figures
5%
10%
(Note 5)
R1
R2
R1
P1
R2
R1
R2
R1
P1
R2
+3.0
1, 5, 6, 9, 12 (4)
4.12
3.01
1.8
0.5
1.2
+100
7
3.57
102
2.2
10
91
+3.6
1, 5, 6, 9, 12 (4)
3.57
3.65
1.5
0.5
1.5
+250
7
3.57
255
2.2
10
240
+5.0
1, 5, 6, 9, 12 (4)
2.15
4.99
0.75
0.5
2.2
-6 (Note 7)
3, (10)
3.57
2.43
1.2
0.5
0.75
+6.0
1, 5, 6, 9, 12 (4)
1.15
6.04
0.5
0.5
2.7
-9
3, 10
3.48
5.36
1.2
0.5
2.0
+9.0
2, 4, (5, 6, 9, 12)
1.87
7.15
0.75
1.0
2.7
-12
3, 10
3.57
8.45
1.2
0.5
3.3
+12
2, 4, (5, 6, 9, 12)
4.87
7.15
2.0
1.0
3.0
-15
3, 10
3.65
11.5
1.2
0.5
4.3
+15
2, 4, (5, 6, 9, 12)
7.87
7.15
3.3
1.0
3.0
-28
3, 10
3.57
24.3
1.2
0.5
10
+28
2, 4, (5, 6, 9, 12)
21.0
7.15
5.6
1.0
2.0
-45
8
3.57
41.2
2.2
10
33
+45
7
3.57
48.7
2.2
10
39
-100
8
3.57
97.6
2.2
10
91
+75
7
3.57
78.7
2.2
10
68
-250
8
3.57
249
2.2
10
240
TABLE 2. Formulae for Intermediate Output Voltages
Outputs from +2 to +7 volts
Outputs from +4 to +250 volts
Current Limiting
(
Figures 1, 4, 5, 6, 9, 12
(
Figure 7)
Outputs from +7 to +37 volts
Outputs from -6 to -250 volts
Foldback Current Limiting
(
Figures 2, 4, 5, 6, 9, 12)
(
Figures 3, 8, 10)
Noise vs Filter Capacitor
(C
REF
in Circuit of
Figure 1)
(Bandwidth 100 Hz to 10 kHz)
DS008563-31
LM723
Power Dissipation vs
Ambient Temperature
DS008563-32
LM723C
Power Dissipation vs
Ambient Temperature
DS008563-33
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