UNISONIC TECHNOLOGIES CO., LTD
LM317A LINEAR INTEGRATED CIRCUIT
www.unisonic.com.tw 1 of 5
Copyright © 2009 Unisonic Technologies Co., Ltd QW-R101-026.D
MEDIUM CURRENT 1.2V TO
37V ADJUSTABLE VOLTAGE
REGULATOR
DESCRIPTION
The UTC LM317A is an adjustable 3-terminal positive voltage
regulator, designed to supply 1.5A of output current with voltage
adjustable from 1.2V ~ 37V.
FEATURES
* Output voltage adjustable from 1.2V ~ 37V
* Output current in excess of 1.5A
* Internal thermal overload protection
* Internal short circuit current limiting
* Output transistor safe area compensation
ORDERING INFORMATION
Ordering Number Pin Assignment
Lead Free Halogen Free Package 1 2 3
Packing
LM317AL-AA3-R LM317AG-AA3-R SOT-223 ADJ O I Tape Reel
LM317AL-TA3-T LM317AG-TA3-T TO-220 ADJ O I Tube
LM317AL-TN3-R LM317AG-TN3-R TO-252 ADJ O I Tape Reel
LM317AL-TQ2-R LM317AG-TQ2-R TO-263 ADJ O I Tape Reel
LM317AL-TQ2-T LM317AG-TQ2-T TO-263 ADJ O I Tube
Note: Pin Assignment: I: VIN O: VOUT
LM317A LINEAR INTEGRATED CIRCUIT
UNISONIC TECHNOLOGIES CO., LTD 2 of 5
www.unisonic.com.tw QW-R101-026.D
BLOCK DIAGRAM
LM317A LINEAR INTEGRATED CIRCUIT
UNISONIC TECHNOLOGIES CO., LTD 3 of 5
www.unisonic.com.tw QW-R101-026.D
ABSOLUTE MAXIMUM RATINGS
PARAMETER SYMBOL RATINGS UNIT
Input-Output Voltage Differential VIN-VOUT 40 V
Power Dissipation PD Internally limited
Junction Temperature TJ +125 °C
Operating Temperature TOPR -40 ~ +85 °C
Storage Temperature TSTG -65 ~ +150 °C
Note: Absolute maximum ratings are those values beyond which the device could be permanently damaged.
Absolute maximum ratings are stress ratings only and functional device operation is not implied.
THERMAL DATA
PARAMETER SYMBOL RATINGS UNIT
SOT-223 140 °C/W
TO-220 50 °C/W
TO-252 103 °C/W
Junction to Ambient
TO-263
θJA
62.5 °C/W
SOT-223 23.5 °C/W
TO-220 3 °C/W
TO-252 12 °C/W
Junction to Case
TO-263
θJC
3 °C/W
ELECTRICAL CHARACTERISTICS
(VIN-VOUT=5V, IOUT=0.5A, PMAX=20W, Ta=25°C, unless otherwise specified.)
PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT
Line Regulation ΔVOUT/VOUT 3V≤VIN-VOUT≤40V, IOUT=100mA 0.01 0.04 %/V
VOUT≤5V 5 25 mV
Load Regulation ΔVOUT 10mA≤IOUT≤1.5A VOUT≥5V 0.1 0.5 %
Adjustable Pin Current IADJ 50 100 μA
Adjustable Pin Current Change ΔIADJ 3V≤VIN-VOUT≤40V,
10mA≤IOUT≤500mA 0.2 5 μA
Reference Voltage VREF 3V≤VIN-VOUT≤40V,
10mA≤IOUT≤1.5A, PD＜PMAX 1.20 1.25 1.30 V
Temperature Stability TMIN≤TJ≤TMAX 0.7 %/VOUT
Minimum Load Current for Regulation IL(MIN) V
IN-VOUT=40V 4.5 mA
VIN-VOUT=40V, PD≤PMAX 0.3 0.4 A
Maximum Output Current IO(MAX) VIN-VOUT=15V, PD＜PMAX 1.5 2.2 A
RMS Noise vs. %of VOUT eN 10HZ≤f≤10KHZ 0.003 %/VOUT
CADJ=0 65 dB
Ripple Rejection RR VOUT=10V,f=120HZ CADJ=10μF 66 80 dB
LM317A LINEAR INTEGRATED CIRCUIT
UNISONIC TECHNOLOGIES CO., LTD 4 of 5
www.unisonic.com.tw QW-R101-026.D
APPLICATION CIRCUITS
1
23 VOUT
R1
R2
VIN
C1
0.1μF
Co
1μF
IADJ
UTC LM317A
VOUT=1.25V×(1+R2/R1)+IADJ×R2
C1 is required when regulator is located an
appreciated distance from power supply. Co is
needed to improve transient response.
1
23 VOUTVIN
D1 1N4002
720Ω
120Ω
1kΩ
1μF
TTL Level
signal
UTC
LM317A
Fig.1 Programmable voltage regulator Fig.2 Regulator with On-off control
mA100<I<mA5
2R+1R
V25.1
=I+)
2R+1R
V
(=I
1R
V25.1
=I+)
1R
V
(=I
OUT
ADJ
REF
)MIN(O
ADJ
REF
)MAX(O
Fig.3 Soft Start Application Fig.4 Constant Current Application
LM317A LINEAR INTEGRATED CIRCUIT
UNISONIC TECHNOLOGIES CO., LTD 5 of 5
www.unisonic.com.tw QW-R101-026.D
TYPICAL CHARACTERISTICS
Output Voltage Deviation, ∆VOUT (%)
Adjustment Current, IADJ (μA)
Min Output Current, IOUT (mA)
Output Current, IOUT (A)
UTC assumes no responsibility for equipment failures that result from using products at values that
exceed, even momentarily, rated values (such as maximum ratings, operating condition ranges, or
other parameters) listed in products specifications of any and all UTC products described or contained
herein. UTC products are not designed for use in life support appliances, devices or systems where
malfunction of these products can be reasonably expected to result in personal injury. Reproduction in
whole or in part is prohibited without the prior written consent of the copyright owner. The information
presented in this document does not form part of any quotation or contract, is believed to be accurate
and reliable and may be changed without notice.
