LM723
HIGH PRECISION VOLTAGE REGULATOR
September 1998
■INPUT VOLTAGEUP TO 40V
■OUTPUT VOLTAGEADJUSTABLE FROM 2
TO 37V
■POSITIVEOR NEGATIVE SUPPLY
OPERATION
■SERIES,SHUNT, SWITCHING OR
FLOATING OPERATION
■OUTPUT CURRENT TO 150mA WITHOUT
EXTERNALPASSTRANSISTOR
■ADJUSTABLECURRENT LIMITING
DESCRIPTION
The LM723 is a monolithic integrated
programmable voltage regulator, assembled in
14-lead dual in-line plastic and SO-14
micropackage. The circuit provides internal
current limiting. When the output current excedes
150mA an external NPN or PNP pass element
may be used.Provisions are made for adjustable
currentlimiting and remote shut-down.
BLOCK DIAGRAM
PlasticDIP-14 SO-14
1/12
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Value Unit
LM723 LM723C
ViDC Input Voltage 40 40 V
∆Vi-o Dropout Voltage 40 40 V
IoOutputCurrent 150 150 mA
Iref Current from Vref 15 25 mA
Top Operating Temperature -55 to 125 0 to 70 oC
Tstg StorageTemperature -65 to 150 -65 to 150 oC
TjJunction Temperature 150 125 oC
PINCONNECTION (top views)
ABSOLUTE MAXIMUM RATINGS
Symbol Parameter Plastic DIP-14 SO-14 Unit
Rthj-amb Thermal Resistance Junction-Ambient Max 200 160 oC/W
TEST CIRCUIT (pin configuration relative to the plastic package)
Vi= 12V
Vo=5V
I
o= 1mA
R1/R2≤10KΩ
ORDER CODES
Type Plastic DIP-14 SO-14
LM723
LM723C LM723N
LM723CN LM723CD
LM723
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ELECTRICAL CHARACTERISTICS FOR LM723C (refer to the testcircuits, Tamb =25o
C,
unless otherwisespecified)
Symbol Parameter Test Conditions Min. Typ. Max. Unit
∆Vo/∆ViLineRegulation Vi= 12 to 15V
Vi= 12 to 40V
Vi= 12 to 15V 0oC≤Tamb ≤70oC
0.01
0.1 0.1
0.5
0.3
%
%
%
∆Vo/VoLoad Regulation Io= 1 to 50 mA
Io= 1 to 10 mA 0oC≤Tamb ≤70oC0.03 0.2
0.6 %
%
VREF Reference Voltage Iref =160 µA6.8 7.15 7.5 V
SVR Supply Voltage Rejection f = 100 Hz to 10KHz Cref =0
f = 100 Hz to 10KHz Cref =5µF74
86 dB
dB
∆Vo/∆T OutputVoltage Drift 150 ppm/oC
Isc OutputCurrent Limit Rsc =10ΩV
o=0 65 mA
ViInput Voltage Range 9.5 40 V
VoOutputVoltage Range 2 37 V
Vo-Vi338V
I
d
Quiescent Current Vi=30V Io=0mA 2.34mA
K
VH Long Term Stability 0.1 %/1000
hrs
eNOutput Noise Voltage BW = 100Hz to 10 KHz Cref =0
BW = 100Hz to 10 KHz Cref =5µF20
2.5 µV
µV
ELECTRICAL CHARACTERISTICS FOR LM723 (refer to the test circuits, Tamb =25o
C,
unless otherwisespecified)
Symbol Parameter Test Conditions Min. Typ. Max. Unit
∆Vo/∆ViLineRegulation Vi= 12 to 15V
Vi= 12 to 40V
Vi= 12 to 15V -55oC≤Tamb ≤125oC
0.01
0.02 0.1
0.2
0.3
%
%
%
∆Vo/VoLoad Regulation Io= 1 to 50 mA
Io= 1 to 10 mA -55oC≤Tamb ≤125oC0.03 0.15
0.6 %
%
VREF Reference Voltage Iref =160 µA6.95 7.15 7.35 V
SVR Supply Voltage Rejection f = 100 Hz to 10KHz Cref =0
f = 100 Hz to 10KHz Cref =5µF74
86 dB
dB
∆Vo/∆T OutputVoltage Drift 150 ppm/oC
Isc OutputCurrent Limit Rsc =10ΩV
o=0 65 mA
ViInput Voltage Range 9.5 40 V
VoOutputVoltage Range 2 37 V
Vo-Vi338V
I
d
Quiescent Current Vi=30V Io=0mA 2.35mA
K
VH Long Term Stability 0.1 %/1000
hrs
eNOutput Noise Voltage BW = 100Hz to 10 KHz Cref =0
BW = 100Hz to 10 KHz Cref =5µF20
2.5 µV
µV
LM723
3/12
Figure3 : Current Limiting Characteristics vs.
JunctionTemperature. Figure 4 : LoadRegulationCharacteristics
without CurrentLimiting.
Figure5 : Load RegulationCharacteristics with
CurrentLimiting. Figure 6 : Load Regulation Characteristics with
Current Limiting
Figure1 : Maximum OutputCurrent vs. Voltage
Drop. Figure 2 : CurrentLimiting Characteristics.
LM723
4/12
Figure9 : QuiescentDrain Current vs. Input
Voltage. Figure 10 : Line Transient Response.
Figure11 : Load TransientResponse. Figure 12 : OutputImpedancevs. Frequency.
Figure7 : LineRegulationvs. VoltageDrop. Figure 8 : Load Regulationvs. Voltage Drop.
LM723
5/12
TABLE 1: ResistorValues (KΩ) for standard OutputVoltages
Output
Voltage Applicable Figures Fixed Output ±5% Output Adjustable ±10% *
R1 R2 R1 P1 R2
+3 13, 16, 17, 18, 21, 23 4.12 3.01 1.8 0.5 1.2
+5 13, 16, 17, 18, 21, 23 2.15 4.99 0.75 0.5 2.2
+6 13, 16, 17, 18, 21, 23 1.15 6.04 0.5 0.5 2.7
+9 14, 16, 17, 18, 21, 23 1.87 7.15 0.75 1 2.7
+12 14, 16, 17, 18, 21, 23 4.87 7.15 2 1 3
+15 14, 16, 17, 18, 21, 23 7.87 7.15 3.3 1 3
+28 14, 16, 17, 18, 21, 23 21 7.15 5.6 1 2
+45 19 3.57 48.7 2.2 10 39
+75 19 3.57 78.7 2.2 10 68
+100 19 3.57 102 2.2 10 91
+250 19 3.57 255 2.2 10 240
-6** 15 3.57 2.43 1.2 0.5 0.75
-9 15 3.48 5.36 1.2 0.5 2
-12 15 3.57 8.45 1.2 0.5 3.3
-15 15 3.65 11.5 1.2 0.5 4.3
-28 15 3.57 24.3 1.2 0.5 10
-45 20 3.57 21.2 2.2 10 33
-100 20 3.57 97.6 2.2 10 91
-250 20 3.57 249 2.2 10 240
Note:
* Replace R1/R2 divider with the circuit of fig24.
** V+must beconnected to a +3V or greater supply.
TABLE 2: Formulaefor Intermediate OutputVoltages
Outputsfrom+2to+7V
Fig.13, 16, 17, 18, 21, 23
VO=[VrefxR2
R1+R2]
Outputs from +4 to +250V
Fig.19
VO=
Vref
2xR2−R1
R1
;R
3=R
4
Current Limiting
ILIMIT =VSENSE
Rsc
Outputs from +7 to +37V
Fig.14, 16, 17, 18, 21, 23
VO=[VrefxR1+R2
R2]
Outputsfrom-6to-250V
Fig.15, 20
VO=
Vref
2xR1+R2
R1
;R
3=R
4
Foldback Current Limiting
IKNEE =
VOR3
Rsc R4xVSENSE(R3+R4)
Rsc R4
ISHORT CKT =
VSENSE
Rsc xR3+R4
R4
LM723
6/12
APPLICATIONINFORMATION (pin numbers relative to the plasticpackage).
Figure13 : BasicLow Voltage Regulator
(Vo= 2 to 7V). Figure 14 : BasicHigh VoltageRegulator
(Vo= 7 to 37V).
Note; R3=
R
1×
R
2
R
1+
R
2for minimum temperaturedrift.
R3 may be eliminated for minimum component count.
Typical performance
RegulatedOutput Voltage.......................... ..........................5V
Line Regulation (∆Vi= 3V).............................................0.5mV
Load Regulation (∆IO= 50mA)................... ................. ...1.5mV
Note; R3=
R
1×
R
2
R
1+
R
2for minimum temperaturedrift.
R3 may be eliminated for minimum componentcount.
Typical performance
Regulated Output Voltage.......................................... ........15V
Line Regulation (∆Vi= 3V).............................................1.5mV
Load Regulation (∆IO= 50mA)....................................... 4.5mV
Figure15 : Negative Voltage Regulator. Figure 16 : PositiveVoltage Regulator (external
Typical performance
Regulated Output Voltage .................... ..............................15V
Line Regulation (∆Vi= 3V).................................................1mV
Load Regulation (∆IO= 100mA)..................... ...................2mV
Typical performance
Regulated Output Voltage...............................................+15V
Line Regulation (∆Vi= 3V)......................................... ....1.5mV
Load Regulation (∆IO= 1A).............................................15mV
LM723
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APPLICATIONINFORMATION (continued).
Figure17 : PositiveVoltage Regulator(External
PNPPass Transistor) Figure 18 : Foldbackcurrent limiting
Typical performance
RegulatedOutput Voltage.......................... ..........................5V
Line Regulation (∆Vi= 3V).............................................0.5mV
Load Regulation (∆IO= 1 A)...........................................1.5mV
Typical performance
Regulated Output Voltage.......................................... .........5 V
Line Regulation (∆Vi= 3V).............................................0.5mV
Load Regulation (∆IO= 10mA).......................................... 1mV
Current LimitKnee..................... ....................................20 mA
Figure19 : PositiveFloating Regulator Figure 20 : NegativeFloatingRegulator
Typical performance
Regulated Output Voltage .................... ...........................100 V
Line Regulation (∆Vi= 20V)........................................... 15 mV
Load Regulation (∆IO= 50mA) ....................... ............... 20 mV
Typical performance
Regulated Output Voltage............................................- 100 V
Line Regulation (∆Vi= 20V)...................... ................. ....30 mV
Load Regulation (∆IO=100 mA)....................................20 mV
LM723
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APPLICATIONINFORMATION (continued).
Figure21 : PositiveSwitching Regulator Figure 22 : RemoteShutdown RegulatorWith
CurrentLimiting
Typical performance
Regulated Output Voltage...................................................5 V
Line Regulation (∆Vi= 30 V).......................................... 10mV
Load Regulation (∆IO= 2 A)...........................................80 mV
Note: current limittransistor may be used for shutdown if
current limiting is notrequired.
Typical performance
Regulated Output Voltage.......................................... .........5 V
Line Regulation (∆Vi= 3 V)....................... ....................0.5 mV
Load Regulation (∆IO= 50 mA)............................. ........ 1.5 mV
Figure23 : ShuntRegulator. Figure 24 : OutputVoltageAdjust
Typical performance
Regulated Output Voltage .................... ...............................5 V
Line Regulation (∆Vi= 10 V)................. ............................2 mV
Load Regulation (∆IO= 100 mA)......................................5 mV
LM723
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DIM. mm inch
MIN. TYP. MAX. MIN. TYP. MAX.
a1 0.51 0.020
B 1.39 1.65 0.055 0.065
b 0.5 0.020
b1 0.25 0.010
D 20 0.787
E 8.5 0.335
e 2.54 0.100
e3 15.24 0.600
F 7.1 0.280
I 5.1 0.201
L 3.3 0.130
Z 1.27 2.54 0.050 0.100
P001A
Plastic DIP-14 MECHANICAL DATA
LM723
10/12
DIM. mm inch
MIN. TYP. MAX. MIN. TYP. MAX.
A 1.75 0.068
a1 0.1 0.2 0.003 0.007
a2 1.65 0.064
b 0.35 0.46 0.013 0.018
b1 0.19 0.25 0.007 0.010
C 0.5 0.019
c1 45 (typ.)
D 8.55 8.75 0.336 0.344
E 5.8 6.2 0.228 0.244
e 1.27 0.050
e3 7.62 0.300
F 3.8 4.0 0.149 0.157
G 4.6 5.3 0.181 0.208
L 0.5 1.27 0.019 0.050
M 0.68 0.026
S 8 (max.)
P013G
SO-14 MECHANICAL DATA
LM723
11/12
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subject to change without notice. This publication supersedes and replaces all information previously supplied. STMicroelectronics products
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LM723
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