PM5342 Datasheet, PDF (128/558 Pages) PMC-Sierra, Inc – SONET/SDH Payload Extractor/Aligner

DATA SHEET
PMC-970133
ISSUE 4
PM5342 SPECTRA-155
SONET/SDH PAYLOAD EXTRACTOR/ALIGNER
4. The VSS, TAVS, RAVS and QAVS ground pins are not internally connected
together. Failure to connect these pins externally may cause malfunction or
damage to the SPECTRA-155.
5. The VDD, TAVD, RAVD and QAVD power pins are not internally connected
together. Failure to connect these pins externally may cause malfunction or
damage to the SPECTRA-155.
6. The TAVD[3:1] and RAVD[4:1] pins provide power to sensitive analog circuitry
in the SPECTRA-155. These signals should be connected to the PCB VDD
power plane at a point where the supply is clean and as free as possible of
digitally induced switching noise. In a typical system, TAVD and RAVD
should be "starred" back to a clean reference point on the PCB, for example
at the card edge connector where the system VDD enters the PCB. In some
systems a clean VDD supply cannot be readily obtained, and RAVD and
TAVD may require separate regulation or filtering as described in the
Operations section.
7. Each TAVD and RAVD pin should be separately decoupled using ceramic
decoupling capacitors located as close as possible to the SPECTRA-155.
8. The TAVS[3:1] and RAVS[4:1] pins provide the ground return path for
sensitive analog circuitry in the SPECTRA-155. These signals should be
connected to the PCB ground plane at a point where the ground is clean and
as free as possible of digital return currents. In a typical system, TAVS and
RAVS should be "starred" back to a clean reference point on the PCB, for
example at the card edge connector where the system ground reference
enters the PCB.
9. Do not exceed 20 mA of current on any I/O pin during the power-up or power-
down sequence. Refer to the Power Sequencing description in the
Operations section.
10. Before any input activity occurs, ensure that the device power supplies are
within their nominal voltage range.
11. Hold the device in the reset condition until the device power supplies are
within their nominal voltage range.
12. Ensure that all digital power is applied simultaneously, and applied before or
simultaneously with the analog power. Refer to the Power Sequencing
description in the Operations section.
13. Reserved Input pins must be strapped low. Failure to connect these pins
may cause malfunction or damage to the SPECTRA-155.
PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE 106