TDA3603P datasheet(6/20 Pages) PHILIPS

6 / 20 page

1997 Aug 15

Philips Semiconductors

Product speciﬁcation

Multiple voltage regulator with switch

TDA3603

FUNCTIONAL DESCRIPTION

The TDA3603 is a multiple output voltage regulator with a

power switch, intended for use in car radios with or without

a microcontroller. Because of low-voltage operation of the

car radio, low-voltage drop regulators are used.

Regulator 2 will switch on when the supply voltage

exceeds 6.5 V for the first time and will switch off again

when the output voltage of regulator 2 is below 1.9 V (this

is below an engine start). When regulator 2 is switched on

and the output voltage of this regulator is within its voltage

range, the reset output will be enabled (reset will go HIGH

via a pull-up resistor) to generate a reset to the

microcontroller. The reset cycles can be extended by an

external capacitor at the reset output (pin 3). The start-up

feature is built-in to ensure a smooth start-up of the

microcontroller at first connection, without uncontrolled

switching of regulator 2 during the start-up sequence.

When both regulator 2 and the supply voltage (VP > 4.5 V)

are available, regulator 1 and the switch can be operated

by an enable input (pin 4).

All output pins are fully protected. The regulators are

protected against load dump (regulator 1 will switch off at

supply voltages higher than 25 V) and short-circuit

(foldback current protection).

The switch contains a current protection which is delayed

for

≥10 ms (in short-circuit condition). During this time the

current is limited to 1.4 A (VP ≤ 18 V).

At supply voltages over 16.9 V the switch is clamped at

15.0 V (to avoid externally connected circuitry being

damaged by an overvoltage) and the switch will switch off

at load dump.

Interfacing with the microcontroller can be accomplished

by an ignition Schmitt trigger and ignition output buffer,

(simple full/semi on/off logic applications).

The total timing of a semi on/off logic set is shown Fig.4.

TDA3603P Datasheet(PDF) 6 Page - NXP Semiconductors