STANDARD PRODUCT
PM4351 COMET
DATA SHEET
PMC-1970624
ISSUE 10
COMBINED E1/T1 TRANSCEIVER
8
PIN DESCRIPTION
Table 1
- Backplane Transmit Interface (4 pins)
Pin Name
Type
Pin No.
-RI -NI
10 D3
Function
BTCLK
I/O
Backplane Transmit Clock (BTCLK). In synchronous backplane applications,
the BTCLK input may be a 1.544 MHz, 2.048 MHz, 3.088 MHz, 4.096 MHz,
8.192 MHz or 16.384 MHz clock with optional gapping for adaptation from non-
uniform system clocks.
BTCLK can be configured as a line-rate output, in which case it is referenced
to TCLKI or the receive recovered clock (loop timed). In T1 NxDS0 mode,
BTCLK is gapped during the framing bit position and optionally for between 1
and 23 DS0 channels in the backplane data stream. In E1 NxDS0 mode,
BTCLK is gapped optionally for between 1 and 31 time slots in the backplane
data stream.
When BTCLK is configured as an input, byte-interleaved backplanes are
supported.
BTCLK may be configured to be active on either its rising or falling edge.
BTPCM and BTSIG are sampled on the active edge of BTCLK. Depending on
its configuration, BTFP is either sampled or updated on the selected active
edge of BTCLK.
After a reset, BTCLK is configured as an input.
PROPRIETARY AND CONFIDENTIAL
19
PMC [ PMC-SIERRA, INC ]
