If Military/Aerospace specified devices are required,
please contact the National Semiconductor Sales Office/
Distributors for availability and specifications.
Power Dissipation
Input-Output Voltage Differential
Operating Junction Temperature
Range
LM137
Internally Limited
40V
−55˚C to +150˚C
Electrical Characteristics
(Note 1)
Parameter
Line Regulation
Load Regulation
Thermal Regulation
Adjustment Pin Current
Adjustment Pin Current Charge
10 mA
≤
I
L
≤
I
MAX
3.0V
≤
|V
IN
− V
OUT
|
≤
40V,
T
A
= 25˚C
Reference Voltage
T
j
= 25˚C (Note 3)
3V
≤
|V
IN
− V
OUT
|
≤
40V, (Note 3)
10 mA
≤
I
OUT
≤
I
MAX
, P
≤
P
MAX
Line Regulation
Load Regulation
Temperature Stability
Minimum Load Current
Current Limit
3V
≤
|V
IN
− V
OUT
|
≤
40V, (Note 2)
10 mA
≤
I
OUT
≤
I
MAX
, (Note 2)
T
MIN
≤
T
j
≤
T
MAX
|V
IN
− V
OUT
|
≤
40V
|V
IN
− V
OUT
|
≤
10V
|V
IN
− V
OUT
|
≤
15V
K, MP and T Package
H Package
|V
IN
− V
OUT
| = 40V, T
j
= 25˚C
K, MP and T Package
H Package
RMS Output Noise, % of V
OUT
Ripple Rejection Ratio
Long-Term Stability
Thermal Resistance, Junction to
Case
Thermal Resistance, Junction to
Ambient (No Heat Sink)
T
j
= 25˚C, 10 Hz
≤
f
≤
10 kHz
V
OUT
= −10V, f = 120 Hz
C
ADJ
= 10 µF
T
j
= 125˚C, 1000 Hours
H Package
K Package
T Package
H Package
K Package
T Package
MP Package
140
35
66
0.24
0.15
0.4
0.17
0.003
60
77
0.3
12
2.3
1
15
3
66
0.15
0.10
0.4
0.17
0.003
60
77
0.3
12
2.3
4
140
35
50
170
1
15
3
A
A
%
dB
dB
%
˚C/W
˚C/W
˚C/W
˚C/W
˚C/W
˚C/W
˚C/W
1.5
0.5
2.2
0.8
3.5
1.8
1.5
0.5
2.2
0.8
3.7
1.9
A
A
0.02
0.3
0.6
2.5
1.2
5
3
0.05
1
0.02
0.3
0.6
2.5
1.5
10
6
0.07
1.5
%/V
%
%
mA
mA
−1.225 −1.250 −1.275 −1.213 −1.250 −1.287
−1.200 −1.250 −1.300 −1.200 −1.250 −1.300
V
V
Conditions
Min
T
j
= 25˚C, 3V
≤
|V
IN
− V
OUT
|
≤
40V
(Note 2) I
L
= 10 mA
T
j
= 25˚C, 10 mA
≤
I
OUT
≤
I
MAX
T
j
= 25˚C, 10 ms Pulse
0.3
0.002
65
2
0.5
0.02
100
5
0.3
0.003
65
2
1.0
0.04
100
5
%
%/W
µA
µA
LM137
Typ
0.01
Max
0.02
Min
LM337
Typ
0.01
Max
0.04
%/V
Units
Note 1:
Unless otherwise specified, these specifications apply −55˚C
≤
T
j
≤
+150˚C for the LM137, 0˚C
≤
T
j
≤
+125˚C for the LM337; V
IN
− V
OUT
= 5V; and I
OUT
= 0.1A for the TO-39 package and I
OUT
= 0.5A for the TO-3, SOT-223 and TO-220 packages. Although power dissipation is internally limited, these specifications
are applicable for power dissipations of 2W for the TO-39 and SOT-223 (see Application Hints), and 20W for the TO-3, and TO-220. I
MAX
is 1.5A for the TO-3,
SOT-223 and TO-220 packages, and 0.2A for the TO-39 package.
Note 2:
Regulation is measured at constant junction temperature, using pulse testing with a low duty cycle. Changes in output voltage due to heating effects are
covered under the specification for thermal regulation. Load regulation is measured on the output pin at a point
1
⁄
8
" below the base of the TO-3 and TO-39 packages.
Note 3:
Selected devices with tightened tolerance reference voltage available.
www.national.com
2
LM137/LM337
Electrical Characteristics
(Note 1)
Schematic Diagram
(Continued)
Note 4:
Refer to RETS137H drawing for LM137H or RETS137K drawing for LM137K military specifications.
00906702
Thermal Regulation
When power is dissipated in an IC, a temperature gradient
occurs across the IC chip affecting the individual IC circuit
components. With an IC regulator, this gradient can be es-
pecially severe since power dissipation is large. Thermal
regulation is the effect of these temperature gradients on
output voltage (in percentage output change) per Watt of
power change in a specified time. Thermal regulation error is
independent of electrical regulation or temperature coeffi-
cient, and occurs within 5 ms to 50 ms after a change in
power dissipation. Thermal regulation depends on IC layout
as well as electrical design. The thermal regulation of a
voltage regulator is defined as the percentage change of
V
OUT
, per Watt, within the first 10 ms after a step of power is
applied. The LM137’s specification is 0.02%/W, max.
00906703
LM137, V
OUT
= −10V
V
IN
− V
OUT
= −40V
I
IL
= 0A
→
0.25A
→
0A
Vertical sensitivity, 5 mV/div
FIGURE 1.
3
www.national.com
LM137/LM337
Thermal Regulation
(Continued)
In
Figure 1,
a typical LM137’s output drifts only 3 mV (or
0.03% of V
OUT
= −10V) when a 10W pulse is applied for
10 ms. This performance is thus well inside the specification
limit of 0.02%/W x 10W = 0.2% max. When the 10W pulse is
ended, the thermal regulation again shows a 3 mV step at
the LM137 chip cools off. Note that the load regulation error
of about 8 mV (0.08%) is additional to the thermal regulation
error. In
Figure 2,
when the 10W pulse is applied for 100 ms,
the output drifts only slightly beyond the drift in the first
10 ms, and the thermal error stays well within 0.1% (10 mV).
00906704
LM137, V
OUT
= −10V
V
IN
− V
OUT
= −40V
I
L
= 0A
→
0.25A
→
0A
Horizontal sensitivity, 20 ms/div
FIGURE 2.
Connection Diagrams
TO-3
Metal Can Package
TO-39
Metal Can Package
00906706
Case Is Input
Note 5:
See STD Mil DWG 5962P99517 for Radiation Tolerant Devices
00906705
Case is Input
Bottom View
Order Number LM137K/883
LM137KPQML and LM137KPQMLV(Note
5)
See NS Package Number K02C
Order Number LM337K STEEL
See NS Package Number K02A
Bottom View
Order Number LM137H, LM137H/883 or LM337H
LM137HPQML and LM137HPQMLV(Note
5)
See NS Package Number H03A
www.national.com
4
LM137/LM337
Connection Diagrams
(Continued)
TO-220
Plastic Package
3-Lead SOT-223
00906734
Front View
Order Number LM337IMP
Package Marked N02A See NS Package Number MP04A
00906707
Front View
Order Number LM337T
See NS Package Number T03B
Application Hints
When a value for
θ
(H−A)
is found using the equation shown,
a heatsink must be selected that has a value that is less than
or equal to this number.
HEATSINKING SOT-223 PACKAGE PARTS
The SOT-223 (“MP”) packages use a copper plane on the
PCB and the PCB itself as a heatsink. To optimize the heat
sinking ability of the plane and PCB, solder the tab of the
package to the plane.
Figures 3, 4
show the information for the SOT-223 package.
Figure 4
assumes a
θ
(J−A)
of 75˚C/W for 1 ounce copper and
51˚C/W for 2 ounce copper and a maximum junction tem-
perature of 125˚C.
00906733
FIGURE 4. Maximum Power Dissipation vs. T
AMB
for
the SOT-223 Package
Please see AN1028 for power enhancement techniques to
