TDA5345HT Datasheet, PDF (29/44 Pages) NXP Semiconductors – 5 V spindle & VCM driver combo

Philips Semiconductors
5 V spindle & VCM driver combo
Supply
Preliminary specification
TDA5345HT
Por5Adj signal
with a capacitor
∆V
PorN
5V
Fig.23 Glitch detector timing _0V
t
Vref=1.23V
t
Tc
t
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.
Vdd5
4.1V
PorN
Tc
VCM-
Fig.23
FCK136
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.
1999 June 10
29