LM317 Datasheet, PDF (1/12 Pages) ON Semiconductor – 1.5 A Adjustable Output, Positive Voltage Regulator

ON Semiconductort
1.5 A Adjustable Output,
Positive Voltage Regulator
The LM317 is an adjustable 3–terminal 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 blow–out 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 Safe–Area Compensation
• Floating Operation for High Voltage Applications
• Available in Surface Mount D²PAK, and Standard 3–Lead Transistor
Package
• Eliminates Stocking many Fixed Voltages
LM317
THREE–TERMINAL
ADJUSTABLE POSITIVE
VOLTAGE REGULATOR
SEMICONDUCTOR
TECHNICAL DATA
T SUFFIX
PLASTIC PACKAGE
CASE 221A
Heatsink surface
connected to Pin 2.
1
2
3
Pin 1. Adjust
2. V_out
3. V_in
V_in
C_in*
0.1 µF
Standard Application
LM317
I_{Adj Adjust}
V_out
R₁
240
+ _CO**
1.0 µF
R₂
**ĂC_in is required if regulator is located an appreciable distance from power supply filter.
**ĂC_O is not needed for stability, however, it does improve transient response.
ǒ Ǔ VoutĂ +Ă 1.25ĂVĂ
1
)
R2
R1
Ă )Ă IAdjĂR2
Since I_Adj is controlled to less than 100 µA, the error associated with this term is
negligible in most applications.
D2T SUFFIX
PLASTIC PACKAGE
CASE 936
(D²PAK)
12
3
Heatsink surface (shown as terminal 4 in
case outline drawing) is connected to Pin 2.
ORDERING INFORMATION
Device
Operating
Temperature Range
Package
LM317BD2T
Surface Mount
T_J = –40° to +125°C
LM317BT
Insertion Mount
LM317D2T
LM317T
Surface Mount
T_J = 0° to +125°C _{Insertion Mount}
© Semiconductor Components Industries, LLC, 2002
1
January, 2002 – Rev. 3
Publication Order Number:
LM317/D