Lm317

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LM117/217 LM317
1.2V TO 37V VOLTAGE REGULATOR

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OUTPUT VOLTAGE RANGE : 1.2 TO 37V OUTPUT CURRENT IN EXCESS OF 1.5A 0.1% LINE AND LOAD REGULATION FLOATING OPERATION FOR HIGH VOLTAGES COMPLETE SERIES OF PROTECTIONS : CURRENT LIMITING, THERMAL SHUTDOWN AND SOA CONTROL

DESCRIPTION The LM117/LM217/LM317 are monolithic integrated circuit in TO-220, TO-220FP, TO-3 and D2PAKpackages intended for use as positive adjustable voltage regulators. They are designed to supply more than 1.5A of load current with an output voltage adjustable over a 1.2 to 37V range. The nominal output voltage is selected by means of only a resistive divider, making the device exceptionally easy to use and eliminating the stocking of many fixed regulators.

TO-3

D2PAK

TO-220

TO-220FPABSOLUTE MAXIMUM RATING
Symbol V i-o IO T op Parameter Input-output Differential Voltage Output Current Operating Junction Temperature for: LM117 LM217 LM317 Power Dissipation Storage Temperature Value 40 Intenrally Limited -55 to 150 -25 to 150 0 to 125 Internally Limited - 65 to 150
o o o

Unit V

C C o C

P tot T st g

C

THERMAL DATA
Symbol Parameter Max Max TO-3 4 35 TO-220 350 TO-220FP 5 60 D2PAK 3 62.5 Unit
o o

R thj- ca se Thermal Resistance Junction-case R thj- amb Thermal Resistance Junction-ambient

C/W C/W

November 2000

1/11

LM117/217/317
CONNECTION DIAGRAM AND ORDERING NUMBERS (top view)

TO-220

TO-220FP

D2PAK

TO-3

Type LM117 LM217 LM317

TO-3 LM117K LM217K LM317K

TO-220 LM217T LM317T

TO-220FP

D PAK LM217D2T

2LM317P

LM317D2T

SCHEMATIC DIAGRAM

2/11

LM117/217/317
BASIC ADJUSTABLE REGULATOR

ELECTRICAL CHARACTERISTICS (Vi - Vo = 5 V, Io = 500 mA, IMAX = 1.5A and PMAX = 20W, unless otherwise specified)
Symbol ∆V o ∆V o Parameter Line Regulation Load Regulation Test Conditions Vi - Vo = 3 to 40 V Vo ≤ 5V Io = 10 mA to IMAX Vo ≥ 5V Io = 10 mA to IMAX I ADJ ∆I ADJ V REF Adjustment Pin CurrentAdjustment Pin Current Vi - Vo = 2.5 to 40 V Io = 10 mA to IMAX Reference Voltage Vi - Vo = 2.5 to 40 V (between pin 3 and pin Io = 10 mA to IMAX 1) PD ≤ PMAX Output Voltage Temperature Stability Minimum Load Current Vi - Vo = 40 V Maximum Load Current Vi - Vo ≤ 15 V PD < PMAX Vi - Vo = 40 V PD < PMAX o Tj = 25 C eN SVR Output Noise Voltage (percentance of VO) Supply Voltage Rejection (*) B = 10Hzto 10KHz Tj = 25 oC Tj = 25 oC f = 120 Hz C ADJ =0 C ADJ =10µF 66 1.5 1.2 T j = 25 o C T j = 25 C T j = 25 C
o o

LM117/LM217 Min. Typ. 0.01 0.02 5 20 0.1 0.3 50 0.2 1.25 Max. 0.02 0.05 15 50 0.3 1 100 5 1.3 1.2 Min.

LM317 Typ. 0.01 0.02 5 20 0.1 0.3 50 0.2 1.25 Max. 0.04 0.07 25 70 0.5 1.5 100 5 1.3

Unit %/V %/V mV mV % % µA µA V

∆ Vo Vo I o (m in) I o (max )

1 3.5 2.2 0.4 5 1.51 3.5 2.2 0.4 10

% mA A A

0.003 65 80 66

0.003 65 80

% dB dB

(*) CADJ is connected between pin 1 and ground. Note: (1) Unless otherwise specified the above specs, apply over the following conditions : LM 117 Tj = – 55 to 150°C; LM 217 Tj = – 25 to 150°C ; LM 317 Tj = 0 to 125°C.

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LM117/217/317
Figure 1 : Output Current vs. Input-output Differential Voltage. Figure 2 :Dropout Voltage vs. Junction Temperature.

Figure 3 : Reference Voltage vs. Junction

Figure 4 : Basic Adjustable Regulator.

APPLICATION INFORMATION The LM117/217/317 provides an internal reference voltage of 1.25V between the output and adjustments terminals. This is used to set a constant current flow across an external resistor divider (see fig. 4), giving an output voltage VO of: R2 VO =VREF (1 + ) + IADJ R2 R1 The device was designed to minimize the term IADJ (100µA max) and to maintain it very constant with line and load changes. Usually, the error term IADJ ⋅ R2 can be neglected. To obtain the previous requirement, all the regulator quiescent current is returned to the output terminal, imposing a minimum load current condition. If the load is insufficient, the output voltage...
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