78P2352 Dual Channel OC-3/STM1-E/E4 Line Interface Unit
PIN DESCRIPTION (CONTINUED)
CONTROL PINS (continued)
NAME
PIN
TYPE DESCRIPTION
Advanced Tx Control 1:
Low: Enables fixed LVPECL equalizer at the transmit inputs SIDP/N (for
FR4 trace lengths up to 1.5m).
Float: Normal operation
1
CIT
TXOUT1
High: Adds 2% positive peaking on leading edge (for bandwidth limiting
components between LIU and coax connector)
Advanced Tx Control 0:
Low: Nominal amplitude
Float: 5% amplitude boost
High: 10% amplitude boost
2
CIT
TXOUT0
Transmitter Power Down:
When high, powers down the transmitter on both channels.
14
77
CID
CID
TXPD
SPSL
Serial Port Selection:
When high, chip is controlled through the serial port.
Reference Clock Frequency Selection:
Selects the reference frequency that is supplied at the CKREFP/N pins. Its
level is read in only at power-up or on the rising edge of a reset signal at the
PORB pin.
81
CIT
CKSL
•
•
•
Low: 19.44MHz or 17.408MHz
Float: 77.76MHz
High: 155.52MHz or 139.264MHz
19
TERIDIAN [ TERIDIAN SEMICONDUCTOR CORPORATION ]
