NSC LM305

LM105/LM205/LM305/LM305A,
LM376 Voltage Regulators
General Description
The LM105 series are positive voltage regulators similar to
the LM100, except that an extra gain stage has been added
for improved regulation. A redesign of the biasing circuitry
removes any minimum load current requirement and at the
same time reduces standby current drain, permitting higher
voltage operation. They are direct, plug-in replacements for
the LM100 in both linear and switching regulator circuits
with output voltages greater than 4.5V. Important characteristics of the circuits are:
Y Output voltage adjustable from 4.5V to 40V
Y Output currents in excess of 10A possible by adding
external transistors
Y Load regulation better than 0.1%, full load with current
limiting
DC line regulation guaranteed at 0.03%/V
Ripple rejection on 0.01%V
Y 45 mA output current without external pass transistor
(LM305A)
Like the LM100, they also feature fast response to both load
and line transients, freedom from oscillations with varying
resistive and reactive loads and the ability to start reliably on
any load within rating. The circuits are built on a single silicon chip and are supplied in a TO-99 metal can.
The LM105 is specified for operation for b55§ C s TA s
a 125§ C, and the LM305/LM305A is specified for 0§ C s TA
s a 70§ C.
Y
Y
Schematic and Connection Diagrams
Metal Can Package
TL/H/7755 – 3
Top View
Order Number LM105H, LM105H/883,
SMD Ý5962-8958801, LM305H or LM305AH
See NS Package Number H08C
TL/H/7755 – 1
C1995 National Semiconductor Corporation
TL/H/7755
RRD-B30M115/Printed in U. S. A.
LM105/LM205/LM305/LM305A, LM376 Voltage Regulators
January 1995
Absolute Maximum Ratings
If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
(Note 5)
LM105
LM305
LM305A
Input Voltage
50V
40V
50V
Input-Output Differential
40V
40V
40V
Power Dissipation (Note 1)
800 mW
800 mW
800 mW
b 55§ C to a 125§ C
b 0§ C to a 70§ C
Operating Temperature Range
0§ C to a 70§ C
b 65§ C to a 150§ C
b 65§ C to a 150§ C
b 65§ C to a 150§ C
Storage Temperature Range
Lead Temperature (Soldering, 10 seconds)
300§ C
300§ C
300§ C
Electrical Characteristics (Note 2)
Parameter
LM105
Conditions
Min
Typ
LM305
Max
Min
Typ
LM305A
Max
Min
Typ
Units
Max
Input Voltage Range
8.5
50
8.5
40
8.5
50
V
Output Voltage Range
4.5
40
4.5
30
4.5
40
V
Input-Output Voltage
Differential
3.0
30
3.0
30
3.0
30
V
Load Regulation
(Note 3)
RSC e 10X, TA e 25§ C
0.02
0.05
0.02
0.05
%
RSC e 10X, TA e TA(MAX)
0.03
0.1
0.03
0.1
%
0.03
0.1
0.03
0.1
%
RSC e 10X, TA e TA(MIN)
0 s IO s 12 mA
0 s IO s 12 mA
RSC e 0X, TA e 25§ C
0.02
0.2
%
RSC e 0X, TA e 70§ C
0.03
0.4
%
RSC e 0X, TA e 0§ C
0.03
0.4
%
0 s IO s 45 mA
Line Regulation
Temperature Stability
TA e 25§ C
%/V
0§ C s TA s a 70§ C
%/V
VIN b VOUT s 5V, TA e 25§ C
0.025
0.06
0.025
0.06
0.025
0.06
%/V
VIN b VOUT t 5V, TA e 25§ C
0.015
0.03
0.015
0.03
0.015
0.03
%/V
0.3
1.0
0.3
1.0
0.3
1.0
%
TA(MIN) s TA s TA(MAX)
2
Electrical Characteristics (Note 2) (Continued)
Parameter
Feedback Sense Voltage
Output Noise Voltage
Standby Current Drain
LM105
Conditions
LM305
Max
Min
Typ
Max
Min
Typ
Max
1.63
1.7
1.81
1.63
1.7
1.81
1.55
1.7
1.85
V
10 Hz s f s 10 kHz
CREF e 0
0.005
0.005
0.005
CREF e 0.1 mF
0.002
0.002
0.002
%
%
VIN e 30V, TA e 25§ C
mA
0.8
VIN e 50V
TA e 25§ C, RSC e 10X,
VOUT e 0V, (Note 4)
225
0.8
2.0
300
375
Long Term Stability
Ripple Rejection
Units
Typ
VIN e 40V
Current Limit
Sense Voltage
LM305A
Min
CREF e 10 mF, f e 120 Hz
225
300
2.0
375
mA
225
0.8
2.0
mA
300
375
mV
0.1
0.1
0.1
%
0.003
0.003
0.003
%/V
iJA
TO-99 Board Mount
in Still Air
230
230
230
§ C/W
iJA
TO-99 Board Mount in
400 LF/Min Air Flow
92
92
92
§ C/W
iJC
TO-99
25
25
25
§ C/W
Note 1: The maximum junction temperature of the LM105 and LM305A is 150§ C, and the LM305 is 85§ C. For operation at elevated temperatures, devices in the
H08C package must be derated based on a thermal resistance of 168§ C/W junction to ambient, or 25§ C/W junction to case. Peak dissipations to 1W are allowable
providing the dissipation rating is not exceeded with the power average over a five second interval for the LM105 and averaged over a two second interval for the
LM305.
Note 2: Unless otherwise specified, these specifications apply for temperatures within the operating temperature range, for input and output voltages within the
range given, and for a divider impedance seen by the feedback terminal of 2 kX. Load and line regulation specifications are for a constant junction temperature.
Temperature drift effects must be taken into account separately when the unit is operating under conditions of high dissipation.
Note 3: The output currents given, as well as the load regulation, can be increased by the addition of external transistors. The improvement factor will be roughly
equal to the composite current gain of the added transistors.
Note 4: With no external pass transistor.
Note 5: Refer to RETS105X Drawing for military specifications for the LM105.
3
Typical Performance Characteristics LM105/LM305/LM305A
Load Regulation
Current Limiting
Characteristics
Current Limit Sense Voltage
Short Circuit Current
Optimum Divider Resistance
Values
Minimum Input Voltage
Regulator Dropout Voltage
Supply Voltage Rejection
Minimum Output Voltage
Standby Current Drain
Transient Response
Load Regulation
TL/H/7755 – 6
4
Typical Applications
10A Regulator with Foldback Current Limiting
² Solid tantalum.
*Electrolytic
TL/H/7755 – 4
1.0A Regulator with Protective Diodes
² Protects against shorted input or inductive leads on
unregulated supply.
*Protects against input voltage reversal.
³ Protects against output voltage reversal.
TL/H/7755 – 5
Linear Regulator with Foldback Current Limiting
Current Regulator
TL/H/7755 – 8
TL/H/7755 – 9
5
Typical Applications (Continued)
Shunt Regulator
TL/H/7755 – 10
Switching Regulator
Basic Positive Regulator with Current Limiting
² Solid tantaium.
³ 125 turns e 22 on Arnold
Engineering A262123-2
molybdenum permally
core. TL/H/7755–11
TL/H/7755 – 12
1.0A Regulator with Protective Diodes
² Protects against shorted
input or inductive loads on
unregulated supply.
*Protects against input
voltage reversal.
³ Protects against output
voltage reversal.
TL/H/7755 – 13
Linear Regulator with Foldback Current Limiting
TL/H/7755 – 14
6
7
LM105/LM205/LM305/LM305A, LM376 Voltage Regulators
Physical Dimensions inches (millimeters)
Metal Can Package (H)
Order Number LM105H, LM105H/883, SMD Ý5962-8958801, LM305H or LM305AH
NS Package Number H08C
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