Fairchild Semiconductor LM337 Datasheet
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LM337
3-Terminal 1.5A Negative Adjustable Regulator
Features
• Output current in excess of 1.5A
• Output voltage adjustable between -1.2V and - 37V
• Internal thermal overload protection
• Internal short circuit current limiting
• Output transistor safe area compensation
• Floating operation for high voltage applications
• Standard 3-pin TO-220 package
Internal Block Diagram
Description
The LM337 is a 3-terminal negative adjustable regulator. It
supplies in excess of 1.5A over an output voltage range of
-1.2V to - 37V. This regulator requires only two external
resistor to set the output voltage. Included on the chip are
current limiting, thermal overload protection and safe area
compensation.
TO-220
1
1. Adj 2. Input 3. Output
Vadj
1
Voltage
Reference
©2001 Fairchild Semiconductor Corporation
3
Output
-
+
Protection
Circuitry
Input
2
Rev. 1.0.0
LM337
Absolute Maximum Ratings
Parameter Symbol Value Unit
Input-Output Voltage Differential |V
Power Dissipation P
Operating Temperature Range T
Storage Temperature Range T
- VO|40 V
I
D
OPR
STG
Internally limited W
0 ~ +125 °C
-65 ~+125 °C
Electrical Characteristics
≤ T
(VI - VO = 5V, IO = 40mA, 0°C
Parameter Symbol Conditions Min Typ. Max. Unit
Line Regulation (Note1) R
Load Regulation (Note1) R
Adjustable Pin Current I
Adjustable Pin Current Change ∆I
Reference Voltage V
Temperature Stability ST
Minimum Load Current to Maintain
Regulation
Output Noise e
Ripple Rejection Ratio RR
Long Term Stability ST T
Thermal Resistance Junction to
Case
≤ +125°C, P
J
load
ADJ
REF
I
L(MIN)
R
θJC
line
ADJ
T
N
= 20W, unless otherwise specified)
DMAX
TA = +25°C
3V ≤
V
I
- VO I ≤ 40V
I
- 0.01 0.04
3V ≤ I VI - VO I ≤ 40V - 0.02 0.07
TA = +25°C
10mA ≤ I
10mA ≤ I
O
O
≤ 0.5A
≤ 1.5A - 15 150
-1550
- - 50 100 µA
TA =+ 25°C
10mA ≤ I
3V ≤I V
=+ 25°C -1.213 -1.250 -1.287
T
A
≤ 1.5A
O
- VO I ≤ 40V
I
3V ≤ I VI - VO I ≤ 40V
10mA ≤ I
≤ 1.5A
O
-25µA
-1.200 -1.250 -1.300 V
0°C ≤ ΤJ ≤ +125°C - 0.6 - %
3V ≤I VI - VO I ≤ 40V - 2.5 10
3V ≤I V
- VO I ≤ 10V - 1.5 6 mA
I
TA =+25°C 10Hz ≤ f ≤10KHz - 0.003 - V/10
V
= -10V, f = 120Hz - 60 -
O
C
= 10µF (Note2) 66 77 - dB
ADJ
= 125°C ,1000Hours - 0.3 1 %
J
--4-°C/ W
%/ V
mV
6
Note:
1. Load and line regulation are specified at constant junction temperature. Change in V
account separately. Pulse testing with low duty is used.
2. C
, when used, is connected detween the adjustment pin and ground.
ADJ
2
O due to heating effects
must be taken into
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