Pin Description

Pin No.

Pin Name

Comments

1V

IN

Positive supply input voltage

2R

t

Sets internal timing currents

3C

t

Sets power-up reset delay timing

4µP

mon

Microcomputer monitor input

5C

mon

Sets µC monitor timing

6

Ground

Regulator ground

7

Reset

Reset error flag output

8

ON/OFF

Enables/disables high current regulators

9V

standby

Standby regulator output (7.5 mA)

10

V

buffer

Buffer regulator output (100 mA)

11

V

OUT

Main regulator output (500 mA)

External Components

Component

Typical Value

Component

Range

Comments

C

IN

1 µF

0.47 µF–10 µF

Required if device is located far from power supply filter.

R

t

130k

24k–510k

Sets internal timing currents.

C

t

0.33 µF

0.033 µF–3.3 µF

Sets power-up reset delay.

C

tc

0.01 µF

0.001 µF–0.1 µF

Establishes time constant of AC coupled computer monitor.

R

tc

10k

1k–100k

Establishes time constant of AC coupled computer monitor. (See

applications section.)

C

mon

0.47 µF

0.047 µF–4.7 µF

Sets time window for computer monitor. Also determines period and pulse

width of computer malfunction reset. (See applications section.)

R

rst

10k

5k–100k

Load for open collector reset output. Determined by computer reset input

requirements.

C

stby

10 µF

10 µF–no bound

A 10 µF is required for stability but larger values can be used to maintain

regulation during transient conditions.

C

buf

10 µF

10 µF–no bound

A 10 µF is required for stability but larger values can be used to maintain

regulation during transient conditions.

C

OUT

10 µF

10 µF–no bound

A 10 µF is required for stability but larger values can be used to maintain

regulation during transient conditions.

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