LM317
DESCRIPTION
3-TERMINAL ADJUSTABLE REGULATORS
The
LM317
are adjustable 3-terminal positive-voltage regulators capable of supplying 1.5A over
a differential voltage range of 3V to 40V. They are exceptionally easy to use and require only two
external resistors to set the output voltage. Both input and output regulation is better than
standard fixed regulators.
In addition to higher performance than fixed regulators, these regulators offer full overload
protection available only in integrated circuits. Included on the chip are current limit, thermal
overload protection, and safe-area protection. All overload protection circuit remains fully
functional even if the adjustment terminal is disconnected. Normally, no capacitors are needed
unless the device is situated far from the input filter capacitors in which case an input bypass is
needed. An optional output capacitor can be added to improve transient response.
The primary applications of each of these regulators is that of a programmable output regulator,
but by connecting a fixed resistor between adjustment terminal and the output terminal, each
device can be used as a precision current regulator. Even though the regulator is floating and
sees only the input-to-output differential voltage, use of these devices to regulate output voltages
that would cause the maximum-rated differential voltage to be exceeded if the output became
shorted is not recommended
TO-220 PACKAGE
LM317T
FEATURES
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Output Voltage Range Adjustable from 1.2 V to 37V
Output Current Capability of 1.5A Max
Input Regulation Typically 0.01% Per Input-Volt
Change
Output Regulation Typically 0.1%
Peak Output Current Constant over Temperature
Range of Regulator
Popular 3-Lead TO-220 AB Package
Ripple Rejection Typically 80 dB
INPUT
OUTPUT
ADJUSTMENT
A
D
I
INPUT
OUTPUT
ADJ
A
O
TO-92
LM317LZ
ABSOLUTE MAXIMUM RATINGS
Input-Output Voltage Differential V
I
- V
O
Operating Junction Temperature Range
Continuous total dissipation at 25℃ free-air temperature
℃
Continuous total dissipation at (or below ) 25℃ case temperature
℃
Storage Temperature
Lead Temperature1.6 mm from case for 10 seconds
I
40V
0℃ to +125℃
℃
℃
2000mW
15W
–65℃ to +150℃
℃
℃
260℃
℃
RECOMMENDED OPERATING CONDITIONS
OUTPUT CURRENT, I
O
OPERATING VIRTUAL JUNCTION TEMPERATURE,T
J
MIN MAX UNIT
10 1500
mA
0
70
℃
Wing Shing Computer Components Co., (H.K.)Ltd.
Homepage:
http://www.wingshing.com
Tel:(852)2341 9276 Fax:(852)2797 8153
E-mail: wsccltd@hkstar.com
WINGS [ WING SHING COMPUTER COMPONENTS ]
