LM317 参数 Datasheet PDF下载

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3-TERMINAL ADJUSTABLE REGULATOR

SLVS044R – SEPTEMBER 1997 – REVISED APRIL 2007

APPLICATION INFORMATION (continued)

R2

720

Ω

ADJUST

V

I

INPUT

OUTPUT

R1

240

Ω

LM317

LM317

INPUT

OUTPUT

ADJUST

V

O

R3

120

Ω

C1

0.1

µF

C2

1

µF

Output

Adjust

R4

1 kΩ

Figure 5. Tracking Preregulator Circuit

LM317

V

I

INPUT

OUTPUT

V

O

R1

1.2 kΩ

ADJUST

R2

20 kΩ

Figure 6. 1.25-V to 20-V Regulator Circuit With Minimum Program Current

LM317

V

I

INPUT

OUTPUT

V

O(1)

R1

120

Ω

V

I

LM317

INPUT

OUTPUT

V

O(1)

V

I

LM317

INPUT

OUTPUT

V

O(1)

ADJUST

ADJUST

ADJUST

R2

1 kΩ

(1) 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

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