LM317

3-TERMINAL ADJUSTABLE REGULATOR

SLVS044H – SEPTEMBER 1997 – REVISED DECEMBER 2001

5

POST OFFICE BOX 655303

APPLICATION INFORMATION

C1

0.1

µF

C3

1

µF

R1

240

Ω

INPUT

OUTPUT

ADJUST

LM317

VO

VI

D1

1N4002

(see Note A)

R2

5 k

Ω

C2

10

µF

NOTE A: D1 discharges C2 if the output is shorted to ground.

Figure 3. Adjustable Regulator Circuit With Improved Ripple Rejection

ADJUST

OUTPUT

INPUT

VI

R1

LM317

I

1.2

R1

Figure 4. Precision Current-Limiter Circuit

C1

0.1

µF

C2

1

µF

R1

240

Ω

INPUT

OUTPUT

ADJUST

LM317

VI

INPUT

OUTPUT

ADJUST

VO

LM317

R2

720

Ω

R3

120

Ω

R4

1 k

Ω

Output

Adjust

Figure 5. Tracking Preregulator Circuit