©2009 Fairchild Semiconductor Corporation
www.fairchildsemi.com
Rev. 1.0.4
Features
• Output Current In Excess of 1.5A
• Output Adjustable Between 1.2V and 37V
• Internal Thermal Overload Protection
• Internal Short Circuit Current Limiting
• Output Transistor Safe Operating Area Compensation
• TO-220 Package
Description
This monolithic integrated circuit is an adjustable 3-terminal
positive voltage regulator designed to supply more than 1.5A
of load current with an output voltage adjustable over a
1.2V to 37V. It employs internal current limiting, thermal
shut-down and safe area compensation.
TO-220
1. Adj 2. Output 3. Input
1
Output
Internal Block Diagram
Rlimit
3Vin
Vo
1
Voltage
Reference
Vad
j
2
Protection
Circuitry
+
-
Input
Output
Adj
LM317
3-Terminal Positive Adjustable Regulator
LM317
2
Absolute Maximum Ratings
Note 1: Absolute Maximum Ratings: are those values beyond which the safety of the device cannot be guaranteed. The device
should not be operated at these limits. The parametric values defined in the Electrical Characteristics tables are not guaranteed
at the absolute maximum ratings. The "Recommended Operating Conditions" table will define the conditions for actual device
operation.
Electrical Characteristics
(VI-VO = 5V, IO = 0.5A, 0°C ≤ TJ ≤ +125°C, IMAX = 1.5A, PDMAX = 20W, unless otherwise specified)
Note 2: Load and line regulation are specified at constant junction temperature . Ch ange in VD due to heating effects must be
taken into account separately. Pulse testing with low duty is used. (PMAX = 20W)
Note 3: CADJ, when used, is connected between the adjustment pin and ground.
Parameter Symbol Value Unit
Input-Output Voltage Differential VI - VO40 V
Lead Temperature TLEAD 230 °C
Power Dissipation PDInternally limited W
Operating Junction Temperature Range Tj0 ~ +125 °C
Storage Temperature Range TSTG -65 ~ +125 °C
Temperature Coefficient of Output Voltage ΔVo/ΔT ±0.02 %/°C
Parameter Symbol Conditions Min. Typ. Max. Unit
Line Regulation (Note2) Rline TA = +25°C
3V ≤ VI - VO ≤ 40V - 0.01 0.04 %/ V
3V ≤ VI - VO ≤ 40V - 0.02 0.07 %/ V
Load Regulation (Note2) Rload
TA = +25°C, 10mA ≤ IO ≤ IMAX
VO< 5V
VO ≥ 5V -18
0.4 25
0.5 mV%/VO
10mA ≤ IO ≤ IMAX
VO < 5V
VO ≥ 5V -40
0.8 70
1.5 mV%/VO
Adjustable Pin Current IADJ - - 46 100 μA
Adjustable Pin Current Change ΔIADJ 3V ≤ VI - VO ≤ 40V
10mA ≤ IO ≤ IMAX PD ≤ PMAX -2.05 μA
Reference Voltage VREF 3V ≤ VIN - VO ≤ 40V
10mA ≤ IO ≤ IMAX
PD ≤ PMAX 1.20 1.25 1.30 V
Temperature Stability STT--0.7-%/V
O
Minimum Load Current to Maintain
Regulation IL(MIN) VI - VO = 40V - 3.5 12 mA
Maximum Output Current IO(MAX) VI - VO ≤ 15V, PD ≤ PMAX
VI - VO ≤ 40V, PD ≤ PMAX
TA=25°C
1.5
-2.2
0.3 -
-A
RMS Noise, % of VOUT eNTA= +25°C, 10Hz ≤ f ≤ 10kHz - 0.003 0.01 %/VO
Ripple Rejection RR VO = 10V, f = 120Hz
without CADJ
CADJ = 10μF (Note3) 66 60
75 -dB
Long-Term Stability, TJ = THIGH ST TA = +25°C for end point
measurements, 1000HR -0.31 %
Thermal Resistance Junction to Case RθJC --5-°C/W
LM317
3
Typical Performance Characteristics
Figure 1. Load Regulation
Figure 3. Dropout Voltage
Figure 2. Adjustment Current
Figure 4. Reference Voltage
TEMPERATURE (°C)
OUTPUT VOLTAGE DEVIATION(%)
TEMPERATURE (°C)
INPUT-OUTPUT DIFFERENTIAL(V)
TEMPERATURE (°C)
ADJUSTMENT CURRENT(uA)
TEMPERATURE (°C)
REFERENCE VOLTAGE(V)
LM317
4
Typical Application
Figure 5. Programmable Regulator
•C
i is required when regulator is located an appreciable distance from power supply filter.
Co is not needed for stability, however, it does improve transient response.
Since IADJ is controlled to less than 100μA, the error as soc i ate d with this term is negligible in most applications.
VI
KA317
Ci
0. 1μF
VI Vo
Vadj
R2
Iadj
VO
= 1.25V (1+ R2/ R1)+Iadj
R2
R1
Iadj
Co
1μF
Input Output
LM317
LM317
5
Mechanical Dimensions
Package Dimensions in millimeters
TO-220 [ SINGLE GAUGE ]
LM317
11/19/09 0. 0m 001
Stock#DS400281
© 2009 Fairchild Semiconductor Corporation
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OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF FAIRCHILD SEMICONDUCTOR
CORPORATION. As used herein:
1. Life support devices or systems are devices or systems
which, (a) are intended for surgical implant into the body,
or (b) support or sustain life, and (c) whose failure to
perform when properly used in accordance with
instructions for use provided in the labeling, can be
reasonably expected to result in a significant injury of the
user.
2. A critical component in any component of a life support
device or system whose failure to perform can be
reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
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FAIRCHILD SEMICONDUCTOR RESERVES THE RIGHT TO MAKE CHANGES WITHOUT FURTHER NOTICE TO ANY
PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRC HILD DOES NOT ASSUME ANY
LIABILITY ARISING OUT OF THE APPLICATION OR USE OF ANY PRODUC T OR CIRCUIT DESCRIBED HEREIN ; NEITHER
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Ordering Information
Product Number Package Operating Temperature
LM317T TO-220 0°C to +125°C
