LM138K-STEEL National Semiconductor Corporation, LM138K-STEEL Datasheet - Page 3

• Manufacturer Part Number: LM138K-STEEL
• Description: 5-amp Adjustable Regulators
• Manufacturer: National Semiconductor Corporation

I
I
V
LOAD
CL
Electrical Characteristics
Note 1: Absolute Maximum Ratings indicate limits beyond which damage to the device may occur. Operating Ratings indicate conditions for which the device is in-
tended to be functional, but do not guarantee specific performance limits. For guaranteed specifications and test conditions, see the Electrical Characteristics.
Note 2: These specifications are applicable for power dissipations up to 50W for the TO-3 (K) package and 25W for the TO-220 (T) package. Power dissipation is
guaranteed at these values up to 15V input-output differential. Above 15V differential, power dissipation will be limited by internal protection circuitry. All limits (i.e.,
the numbers in the Min. and Max. columns) are guaranteed to National’s AOQL (Average Outgoing Quality Level).
Note 3: Regulation is measured at a constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are
covered under the specifications for thermal regulation.
Note 4: Refer to RETS138K drawing for military specifications of LM138K.
JC
JA
V
N
Typical Performance Characteristics
Current Limit
Load Regulation
Symbol
R/T
(Min)
Temperature Stability
Minimum Load Current
Current Limit
RMS Output Noise, % of V
Ripple Rejection Ratio
Long-Term Stability
Thermal Resistance
Junction to Case
Thermal Resistance, Junction to
Ambient (No Heat Sink)
Parameter
DS009060-32
DS009060-35
OUT
(Continued)
Current Limit
Dropout Voltage
T
V
V
V
10 Hz
V
V
T
K Package
T Package
K Package
T Package
MIN
J
IN
IN
IN
OUT
OUT
DC
0.5 ms Peak
= 125˚C, 1000 hrs
− V
− V
− V
= 10V, f = 120 Hz, C
= 10V, f = 120 Hz, C
T
OUT
OUT
OUT
J
f
3
10 kHz
= 35V
= 30V
T
MAX
Conditions
10V
DS009060-33
DS009060-36
ADJ
ADJ
= 0 µF
= 10 µF
Current Limit
Adjustment
Current
Min
60
5
7
LM338
0.003
Typ
3.5
0.3
12
60
75
35
50
1
8
Max
www.national.com
10
1
1
1
4
DS009060-34
DS009060-37
Units
˚C/W
˚C/W
˚C/W
˚C/W
mA
dB
dB
%
%
%
A
A
A