STAC9752A Datasheet, PDF (23/106 Pages) Integrated Device Technology – AC’97 2.3 CODECS WITH STEREO MICROPHONE & UNIVERSAL JACK

STAC9752A/9753A
AC’97 2.3 CODECS WITH STEREO MICROPHONE & UNIVERSAL JACK
PC AUDIO
3.3. Split Independent Power Supply Operation
In PC applications, one power supply input to the STAC9752A/9753A may be derived from a supply
regulator and the other directly from the PCI power supply bus. When power is applied to the PC, the
regulated supply input to the IC will be applied some time delay after the PCI power supply. Without
proper on-chip partitioning of the analog and digital circuitry, some manufacturer's CODECs would
be subject to on-chip SCR type latch-up.
IDT’s STAC9752A/9753A specifically allows power-up sequencing delays between the analog
(AVddx) and digital (VDddx) supply pins. These two power supplies can power-up independently
and at different rates with no adverse effects to the CODEC. The IC is designed with independent
analog and digital circuitry that prevents on-chip SCR type latch-up.
However, the STAC9752A/9753A is not designed to operate for extended periods with only the ana-
log supply active.
IDT™
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AC’97 2.3 CODECS WITH STEREO MICROPHONE & UNIVERSAL JACK
STAC9752A/9753A
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