Block Diagram

TLH8821 – 2

Pin Description

Pin No

Pin Name

Comments

Positive supply input voltage

Sets internal timing currents

Sets power-up reset delay timing

4

m

Microcomputer monitor input

Sets mC monitor timing

6

Ground

Regulator ground

7

Reset

Reset error flag output

8

ONOFF

Enablesdisables high current regulators

Standby regulator output (75 mA)

10

Buffer regulator output (100 mA)

11

Main regulator output (500 mA)

External Components

Component

Typical Value

Component Range

Comments

1 mF

047 mF–10 mF

Required if device is located far from power supply filter

130k

24k – 12M

Sets internal timing currents

033 mF

0033 mF – 33 mF

Sets power-up reset delay

001 mF

0001 mF – 01 mF

Establishes time constant of AC coupled computer monitor

10k

1k – 100k

Establishes time constant of AC coupled computer monitor (See

applications section)

047 mF

0047 mF – 47 mF

Sets time window for computer monitor Also determines period and pulse

width of computer malfunction reset (See applications section)

10k

5k – 100k

Load for open collector reset output Determined by computer reset input

requirements

10 mF10 mF – no bound

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

regulation during transient conditions

10 mF10 mF – no bound

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

regulation during transient conditions

10 mF10 mF – no bound

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

regulation during transient conditions

6