Philips Semiconductors

PIP3221-DC

Dual channel high-side TOPFET™

Product data

Rev. 01 — 20 February 2004

4 of 16

9397 750 12361

© Koninklijke Philips Electronics N.V. 2004. All rights reserved.

5.

Functional description

A diagnostic status ensures faster fault detection.

Active current limit is combined with a soft latched short circuit protection feature in

order to protect the device in the event of a short circuit.

Thermal shutdown for high temperature conditions has an automatic restart at a

lower temperature so providing protection against excessive power dissipation.

Active clamping protects the device against low energy spikes.

Undervoltage lockout means the device shuts down for low battery voltages, thus

avoiding faulty operation.

Overvoltage shutdown in the on-state protects a load such as a lamp filament from

potentially destructive voltage spikes.

[1]

The status will continue to indicate OT (even if the input goes LOW) until the device cools below the reset threshold temperature.

See “Overtemperature protection” characteristics in Table 7 “Static characteristics”.

Table 4:

Truth table

Abbreviations: L = logic LOW; H = logic HIGH; X = don’t care; 0 = condition not present; 1 = condition present;

UV = undervoltage; OV = overvoltage; OC = open circuit load; SC = short circuit; OT = overtemperature [1].

Input

Supply

Load 1

Load 2

Load output

Status Operating mode

1

2

UV

OV

OC

SC

OT

OC

SC

OT

1

2

L

L

0

X

0

X

X

0

X

X

OFF

OFF

H

both off & normal

L

L

0

X

1

XXXXX

OFF

OFF

L

both off, one/both OC or

Figure 10

L

H

0

X

1

X

X

0

0

0

OFF

ON

L

one off & OC, with other on

& normal

H

L00000000

ON

OFF

H

one on & normal, with other

off & normal

H

H

00000000

ON

ON

H

both on & normal

H

X

1

0

X

X

X

0

X

X

OFF

OFF

H

supply undervoltage lockout

H

X

0

1

X

0

0

X

0

0

OFF

OFF

H

supply overvoltage

shutdown

H

X

0001

XXXX

OFF

X

L

one SC shutdown

H

L0001

X

0

0

X

OFF

OFF

L

one SC shutdown, with other

off & normal

H

H

0001

X

000

OFF

ON

L

one SC shutdown, with other

on & normal

H

X

00001

X

X

X

OFF

X

L

one OT shutdown

H

L0000100

X

OFF

OFF

L

one OT shutdown, with other

off & normal

H

H

00001000

OFF

ON

L

one OT shutdown, with other

on & normal