1999 June 10

29

Philips Semiconductors

Preliminary specification

5 V spindle & VCM driver combo

TDA5345HT

The PorN output can also be driven by the retract sequence manager:

If there is a power supply failure at the sequence start-up or during the sequence, PorN will be kept low during all the

programmed sequence, what ever the supply is restored or not.

Caution !!

It is not allowed to wake the VCM up ( VcmSleep = ‘0’’) if the spindle is not on speed, because a retract sequence would

start on a power supply failure without any clock (generated from the spindle back-EMF). PorN would be maintained low

by the retract manager, waiting for clock pulses.

Fig.23 Glitch detector timing

t

Supply

∆V

Tc

t

t

PorN

Por5Adj signal

Vref=1.23V

with a capacitor

5V

0V

VCM-

FCK136

Tc

PorN

Vdd5

4.1V

Fig.23