PM7375-SC datasheet(56/430 Pages) PMC

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PM7375 LASAR-155

DATA SHEET

PMC-931127

ISSUE 6

LOCAL ATM SAR & PHYSICAL LAYER

PROPRIETARY AND CONFIDENTIAL TO PMC-SIERRA, INC., AND FOR ITS CUSTOMERS’ INTERNAL USE

Notes on Pin Description:

All LASAR-155 inputs and bidirectionals present minimum capacitive loading

and operate at TTL logic levels, with the exception of RXPHYBP and TXPHYBP

I/O which are CMOS.

Most LASAR-155 digital outputs and bidirectionals have 4 mA drive capability,

except the PCICLKO, TXD+ and TXD- outputs which have 8 mA drive

capability; and the PCI outputs which have standard PCI drive capability.

Inputs RSTB, ROMP, TMS, TDI and TRSTB have internal pull-up resistors.

The VSS_DC, VSS_AC, TXVSS, TAVS and RAVS ground pins are not

internally connected together. Failure to connect these pins externally may

cause malfunction or damage to the LASAR-155.

The VDD_DC , VDD_AC, TXVDD, TAVD and RAVD power pins are not

internally connected together. Failure to connect these pins externally may

cause malfunction or damage to the LASAR-155.

The TAVD[3:1] and RAVD[4:1] pins provide power to sensitive analog circuitry

in the LASAR-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.

Each TAVD and RAVD pin should be separately decoupled using ceramic

decoupling capacitors located as close as possible to the LASAR-155.

The TAVS[3:1] and RAVS[4:1] pins provide the ground return path for sensitive

analog circuitry in the LASAR-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.

Do not exceed 100 mA of current on any pin during the power-up or power-

down sequence. Refer to the Power Sequencing description in the Operations

section.

PM7375-SC Datasheet(PDF) 56 Page - PMC-Sierra, Inc