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LM117 / 217 LM317

1.2V TO 37V ADJUSTABLE VOLTAGE REGULATOR

LM117 / 217 LM317
1.2V TO 37V ADJUSTABLE VOLTAGE REGULATOR
DESCRIPTION The LM117 / LM217 / LM317 are monolithic integrated circuit in TO-220 and TO-3 packages 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. ABSOLUTE MAXIMUM RATING
Symbol Vi-o IO Top Output Current Operating Junction Temperature for: LM117 LM217 LM317 Parameter Input-output Differential Voltage
TO-220
TO-39
Value 40 Intenrally Limited -55 to 150 -25 to 150 0 to 125 Internally Limited
Unit V
Power Dissipation
THERMAL DATA
TO-3 Rthj-case Thermal Resistance Junction-case Rthj-amb Thermal Resistance Junction-ambient Max Max 4 35 TO-220 3 50 ISOWATT220 4 60 TO-39 15 160
March 1993
LM117 / LM217 / LM317
PIN CONNECTION AND ORDERING NUMBER TO-220 TO-3 TO-3
SCHEMATIC DIAGRAM
LM117 / LM217 / LM317
Basic adjustable regulator.
Vo Vo Io(min) Io(max)
() CADJ is connected between pin 1 and ground.
LM117 / LM217 / LM317
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.
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 will rise. Since the LM117 / 217317 is a floating regulator and "sees" only the input-to-output differential voltage,
supplies of very high voltage with respect to ground can be regulated as long as the maximum input-tooutput differential is not exceeded. Furthermore, programmable regulator are easily obtainable and, by connecting a fixed resistor between the adjustment and output, the device can be used as a precision current regulator. In order to optimise the load regulation, the current set resistor R1 (see fig. 4) should be tied as close as possible to the regulator, while the ground terminal of R2 should be near the ground of the load to provide remote ground sensing. No external capacitors are required, but performance may be improved with added capacitance as follow: An input bypass capacitor of 0.1 µF
LM117 / LM217 / LM317
An adjustment terminal to ground 10 mF capacitor to improve the ripple rejection of about 15 dB (CADJ). An 1mF tantalium capacitor on the output to improve transient response. In additional to external capacitors, it is good practice to add protection diodes, as shown in fig.5. D1 protect the device against input short circuit, while D2 protect against output short circuit for capacitance discharging.
Figure 5 : Voltage Regulator with Protection Diodes.
D1 protect the device against input short circuit, while D2 protects against output short circuit for capacitors discharging
Figure 6 : Slow Turn-on 15V Regulator.
Figure 7 : Current Regulator.
Vref 1.25V + IADJ R1 R1
LM117 / LM217 / LM317
Figure 8 : 5V Electronic Shut-down Regulator. Figure 9 : Digitally Selected Outputs.
(R2 sets maximum Vo )
Figure 10 : Battery Charger (12V).
Figure 11 : Current Limited 6V Charger.
R3 sets peak current (0.6A for 1). C1 recommended to filter out input transients.
LM117 / LM217 / LM317
TO-3 MECHANICAL DATA
mm MIN. A B C D E G N P R U V 11.00 0.97 1.50 8.32 19.00 10.70 16.50 25.00 4.00 38.50 30.00 TYP. MAX. 13.10 1.15 1.65 8.92 20.00 11.10 17.20 26.00 4.09 39.30 30.30 MIN. 0.433 0.038 0.059 0.327 0.748 0.421 0.649 0.984 0.157 1.515 1.187 inch TYP. MAX. 0.516 0.045 0.065 0.351 0.787 0.437 0.677 1.023 0.161 1.547 1.193
P003F
LM117 / LM217 / LM317
TO-220 MECHANICAL DATA
DIM. MIN. A C D D1 E F F1 F2 G G1 H2 L2 L4 L5 L6 L7 L9 DIA. 13.0 2.65 15.2 6.2 3.5 3.75 0.49 0.61 1.14 1.14 4.95 2.4 10.0 16.4 14.0 2.95 15.9 6.6 4.2 3.85 0.511 0.104 0.598 0.244 0.137 0.147 4.40 1.23 2.40 1.27 0.70 0.88 1.70 1.70 5.15 2.7 10.40 0.019 0.024 0.044 0.044 0.194 0.094 0.393 0.645 0.551 0.116 0.625 0.260 0.165 0.151 mm TYP. MAX. 4.60 1.32 2.72 MIN. 0.173 0.048 0.094 0.050 0.027 0.034 0.067 0.067 0.203 0.106 0.409 inch TYP. MAX. 0.181 0.051 0.107
Dia. F2 F
P011C
LM117 / LM217 / LM317
TO39 MECHANICAL DATA
mm DIM. MIN. A B D E F G H I L 5.08 1.2 0.9 45o (typ.) 12.7 0.49 6.6 8.5 9.4 0.200 0.047 0.035 TYP. MAX. MIN. 0.500 0.019 0.260 0.334 0.370 TYP. MAX. inch
P008B
LM117 / LM217 / LM317