LM317M
500 mA Adjustable Output,
Positive Voltage Regulator
The LM317M is an adjustable three−terminal positive voltage
regulator capable of supplying in excess of 500 mA 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 blow−out
proof.
The LM317M serves a wide variety of applications including local,
on−card regulation. This device also makes an especially simple
adjustable switching regulator, a programmable output regulator, or by
connecting a fixed resistor between the adjustment and output, the
LM317M can be used as a precision current regulator.
Features
http://onsemi.com
Heatsink surface
connected to Pin 2
TO−220AB
T SUFFIX
CASE 221A
1
2
3
•
•
•
•
•
•
•
•
Output Current in Excess of 500 mA
Output Adjustable between 1.2 V and 37 V
Internal Thermal Overload Protection
Internal Short Circuit Current Limiting
Output Transistor Safe−Area Compensation
Floating Operation for High Voltage Applications
Eliminates Stocking Many Fixed Voltages
Pb−Free Packages are Available
SOT−223
ST SUFFIX
CASE 318E
1
2
3
4
DPAK
DT SUFFIX
CASE 369C
1 2
3
V
in
V
in
LM317M
V
out
V
out
R
1
240
Heatsink Surface (shown as terminal 4 in
case outline drawing) is connected to Pin 2.
*
C
in
0.1mF
I
Adj
Adjust
**
+C
O
1.0mF
PIN ASSIGNMENT
1
2
3
Adjust
V
out
V
in
R
2
ORDERING INFORMATION
* = 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.
R
Vout
+
1.25 V 1
)
2
)
IAdj R2
R1
Since I
Adj
is controlled to less than 100
mA,
the error associated with this
term is negligible in most applications.
See detailed ordering and shipping information in the package
dimensions section on page 12 of this data sheet.
DEVICE MARKING INFORMATION
See general marking information in the device marking
section on page 13 of this data sheet.
Figure 1. Simplified Application
©
Semiconductor Components Industries, LLC, 2004
1
August, 2004 − Rev. 12
Publication Order Number:
LM317M/D
ONSEMI [ ON SEMICONDUCTOR ]
