1.5 A Adjustable Output,
Positive Voltage Regulator
The LM317 is an adjustable 3terminal positive voltage regulator
capable of supplying in excess of 1.5 A over an output voltage range of
1.2 V to 37 V. This voltage regulator is exceptionally easy to use and
requires only two external resistors to set the output voltage. Further, it
employs internal current limiting, thermal shutdown and safe area
compensation, making it essentially blowout proof.
The LM317 serves a wide variety of applications including local, on
card regulation. This device can also be used to make a programmable
output regulator, or by connecting a fixed resistor between the
adjustment and output, the LM317 can be used as a precision current
regulator.
Output Current in Excess of 1.5 A
Output Adjustable between 1.2 V and 37 V
Internal Thermal Overload Protection
Internal Short Circuit Current Limiting Constant with Temperature
Output Transistor SafeArea Compensation
Floating Operation for High Voltage Applications
Available in Surface Mount D
2
PAK, and Standard 3Lead Transistor
Package
Eliminates Stocking many Fixed Voltages
Standard Application
*
* C
in
is required if regulator is located an appreciable distance from power supply filter.
** C
O
is not needed for stability, however, it does improve transient response.
Since I
Adj
is controlled to less than 100
A, the error associated with this term is
negligible in most applications.
Vout + 1.25 V 1 )
R2
R1
) IAdj R2
LM317
V
in
V
out
R
1
240
R
2
Adjust
I
Adj
C
in
*
0.1
F
+ C
O
**
1.0
F
ON Semiconductort
Semiconductor Components Industries, LLC, 2002
January, 2002 Rev. 3
1
Publication Order Number:
LM317/D
SEMICONDUCTOR
TECHNICAL DATA
THREETERMINAL
ADJUSTABLE POSITIVE
VOLTAGE REGULATOR
Device
Operating
Temperature Range
Package
T SUFFIX
PLASTIC PACKAGE
CASE 221A
ORDERING INFORMATION
LM317BT
LM317BD2T
Insertion Mount
Surface Mount
LM317T
LM317D2T
T
J
= 0
to +125
C
Insertion Mount
Surface Mount
T
J
= 40
to +125
C
Pin 1. Adjust
2. V
out
3. V
in
D2T SUFFIX
PLASTIC PACKAGE
CASE 936
(D
2
PAK)
Heatsink surface (shown as terminal 4 in
case outline drawing) is connected to Pin 2.
3
1
2
Heatsink surface
connected to Pin 2.
LM317
3
1
2
LM317
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2
MAXIMUM RATINGS
Rating
Symbol
Value
Unit
InputOutput Voltage Differential
V
I
V
O
40
Vdc
Power Dissipation
Case 221A
T
A
= +25
C
P
D
Internally Limited
W
Thermal Resistance, JunctiontoAmbient
JA
65
C/W
Thermal Resistance, JunctiontoCase
JC
5.0
C/W
Case 936 (D
2
PAK)
T
A
= +25
C
P
D
Internally Limited
W
Thermal Resistance, JunctiontoAmbient
JA
70
C/W
Thermal Resistance, JunctiontoCase
JC
5.0
C/W
Operating Junction Temperature Range
T
J
40 to +125
C
Storage Temperature Range
T
stg
65 to +150
C
ELECTRICAL CHARACTERISTICS
(V
I
V
O
= 5.0 V; I
O
= 0.5 A for D2T and T packages; T
J
= T
low
to T
high
[Note 1]; I
max
and P
max
[Note 2]; unless otherwise noted.)
Characteristics
Figure
Symbol
Min
Typ
Max
Unit
Line Regulation (Note 3), T
A
= +25
C, 3.0 V
V
I
V
O
40 V
1
Reg
line
0.01
0.04
%/V
Load Regulation (Note 3), T
A
= +25
C, 10 mA
I
O
I
max
V
O
5.0 V
V
O
5.0 V
2
Reg
load
5.0
0.1
25
0.5
mV
% V
O
Thermal Regulation, T
A
= +25
C (Note 6), 20 ms Pulse
Reg
therm
0.03
0.07
% V
O
/W
Adjustment Pin Current
3
I
Adj
50
100
A
Adjustment Pin Current Change, 2.5 V
V
I
V
O
40 V,
10 mA
I
L
I
max
, P
D
P
max
1, 2
I
Adj
0.2
5.0
A
Reference Voltage, 3.0 V
V
I
V
O
40 V,
10 mA
I
O
I
max
, P
D
P
max
3
V
ref
1.2
1.25
1.3
V
Line Regulation (Note 3), 3.0 V
V
I
V
O
40 V
1
Reg
line
0.02
0.07
% V
Load Regulation (Note 3), 10 mA
I
O
I
max
V
O
5.0 V
V
O
5.0 V
2
Reg
load
20
0.3
70
1.5
mV
% V
O
Temperature Stability (T
low
T
J
T
high
)
3
T
S
0.7
% V
O
Minimum Load Current to Maintain Regulation (V
I
V
O
= 40 V)
3
I
Lmin
3.5
10
mA
Maximum Output Current
V
I
V
O
15 V, P
D
P
max,
T Package
V
I
V
O
= 40 V, P
D
P
max
, T
A
= +25
C, T Package
3
I
max
1.5
0.15
2.2
0.4
A
RMS Noise, % of V
O
, T
A
= +25
C, 10 Hz
f
10 kHz
N
0.003
% V
O
Ripple Rejection, V
O
= 10 V, f = 120 Hz (Note 4)
Without C
Adj
C
Adj
= 10
F
4
RR
66
65
80
dB
LongTerm Stability, T
J
= T
high
(Note 5), T
A
= +25
C for
Endpoint Measurements
3
S
0.3
1.0
%/1.0 k
Hrs.
Thermal Resistance Junction to Case, T Package
R
JC
5.0
C/W
NOTES: 1. T
low
to T
high
= 0
to +125
C, for LM317T, D2T. T
low
to T
high
= 40
to +125
C, for LM317BT, BD2T.
2. I
max
= 1.5 A, P
max
= 20 W
3. Load and line regulation are specified at constant junction temperature. Changes in V
O
due to heating effects must be taken into account separately.
Pulse testing with low duty cycle is used.
4. C
Adj
, when used, is connected between the adjustment pin and ground.
5. Since LongTerm Stability cannot be measured on each device before shipment, this specification is an engineering estimate of average stability
from lot to lot.
6. Power dissipation within an IC voltage regulator produces a temperature gradient on the die, affecting individual IC components on the die. These
effects can be minimized by proper integrated circuit design and layout techniques. Thermal Regulation is the effect of these temperature gradients
on the output voltage and is expressed in percentage of output change per watt of power change in a specified time.
LM317
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3
Representative Schematic Diagram
This device contains 29 active transistors.
31
0
310
230
120
5.6k
V
in
170
6.3V
160
12k
5.0pF
6.8k
13k
6.3V
105
4.0
0.1
V
out
Adjust
12.5k
2.4k
30
pF
30
pF
6.3V
125k
135
190
12.4k
3.6k 5.8k 110
5.1k
6.7k
510
200
Figure 1. Line Regulation and
I
Adj
/Line Test Circuit
* Pulse testing required.
*
1% Duty Cycle
*
is suggested.
*
V
CC
V
IH
V
IL
V
in
V
out
R
L
+
1.0
F
C
O
240
1%
R
1
Adjust
R
2
1%
C
in
0.1
F
I
Adj
LM317
Line Regulation (% V) +
|VOH VOL|
|VOL|
x 100
V
OH
V
OL
LM317
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4
Figure 2. Load Regulation and
I
Adj
/Load Test Circuit
Figure 3. Standard Test Circuit
Figure 4. Ripple Rejection Test Circuit
V
O
LM317
V
O
(min Load)
- V
O
(max Load)
* Pulse testing required.
*
1% Duty Cycle is suggested.
Load Regulation (mV) = V
O
(min Load) - V
O
(max Load)
Load Regulation (% V
O
) =
x 100
V
O
(min Load)
V
O
(max Load)
C
in
0.1
F
Adjust
R
2
1%
C
O
1.0
F
+
*
R
L
(max Load)
R
L
(min Load)
V
out
R
1
240
1%
V
I
V
in
I
Adj
I
L
* Pulse testing required.
*
1% Duty Cycle is suggested.
V
in
V
out
Adjust
R
1
240
1%
+
1.0
F
C
O
R
L
C
in
R
2
1%
To Calculate R
2
: V
out
= I
SET
R
2
+ 1.250 V
To Calculate R
2
:
Assume I
SET
= 5.25 mA
I
L
I
Adj
I
SET
V
ref
V
O
V
I
0.1
F
V
in
V
out
V
out
= 10 V
R
L
C
in
0.1
F
Adjust
R
1
240
1%
D
1
*
1N4002
C
O
+
1.0
F
24 V
14 V
R
2
1.65 k
1%
C
Adj
10
F
+
* D
1
Discharges C
Adj
if output is shorted to Ground.
f = 120 Hz
LM317
LM317
V
O
(min Load)
LM317
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5
Figure 5. Load Regulation
Figure 6. Current Limit
Figure 7. Adjustment Pin Current
Figure 8. Dropout Voltage
Figure 9. Temperature Stability
Figure 10. Minimum Operating Current
V out
, OUTPUT
VOL
T
AGE CHANGE (%)
V
in
= 15 V
V
out
= 10 V
I out
, OUTPUT
CURRENT
(A)
,
ADJUSTMENT
PIN CURRENT
(
A)
Adj
I
, INPUT-OUTPUT
VOL
T
AGE
in
out
V-
V
refV
,
REFERENCE VOL
T
AGE (V)
I B
, QUIESCENT
CURRENT
(mA)
DIFFERENTIAL
(Vdc)
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
4.0
3.0
2.0
1.0
0
70
65
60
55
50
45
40
35
3.0
2.5
2.0
1.5
1.0
1.26
1.25
1.24
1.23
1.22
5.0
4.5
4.0
3.5
3.0
2.5
2.0
1.5
1.0
0.5
0
-50
-25
0
25
50
75
100 125
150
T
J
, JUNCTION TEMPERATURE (
C)
0
10
20
30
40
V
in
-V
out
, INPUT-OUTPUT VOLTAGE DIFFERENTIAL (Vdc)
-50 -25
0
25
50
75
100 125 150
T
J
, JUNCTION TEMPERATURE (
C)
-50 -25
0
25
50
75
100 125 150
T
J
, JUNCTION TEMPERATURE (
C)
-50 -25
0
25
50
75
100 125 150
T
J
, JUNCTION TEMPERATURE (
C)
0
10
20
30
40
V
in
-V
out
, INPUT-OUTPUT VOLTAGE DIFFERENTIAL (Vdc)
1.0 A
+150
C
I
L
= 0.5 A
I
L
= 1.5 A
55
C
150
C
T
J
= 25
C
V
out
= 100 mV
I
L
= 1.5 A
500 mA
200 mA
20 mA
+25
C
T
J
= -55
C
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