LM317

3-TERMINAL ADJUSTABLE REGULATOR

SLVS044H – SEPTEMBER 1997 – REVISED DECEMBER 2001

6

POST OFFICE BOX 655303

APPLICATION INFORMATION

R1

1.2 k

Ω

R2

20 k

Ω

INPUT

OUTPUT

ADJUST

LM317

VO

VI

Figure 6. 1.2-V to 20-V Regulator Circuit With Minimum Program Current

INPUT

OUTPUT

ADJUST

LM317

VO†

VI

INPUT

OUTPUT

ADJUST

LM317

VO†

VI

INPUT

OUTPUT

ADJUST

LM317

VO†

VI

R1

120

Ω

R2

1 k

Ω

† Minimum load current from each output is 10 mA. All output voltages are within 200 mV of each other.

Figure 7. Adjusting Multiple On-Card Regulators With a Single Control

R1

240

Ω

R2

2.4 k

Ω

INPUT

OUTPUT

ADJUST

LM317

VI

RS

0.2

Ω

(see Note A)

NOTE A: RS controls the output impedance of the charger.

The use of RS allows for low charging rates with a fully charged battery.

Z

R2

R1

Figure 8. Battery-Charger Circuit