78P2352 Dual Channel OC-3/STM1-E/E4 Line Interface Unit
PIN DESCRIPTION (CONTINUED)
SERIAL-PORT PINS
NAME
PIN TYPE DESCRIPTION
[SPSL=1] Serial-Port Enable:
High during read and write operations. Low disables the serial port.
While SEN is low, SDO remains in high impedance state, and SDI and
SCK activities are ignored.
[SPSL=0] Medium Select:
SEN_CMI
95
96
CIT
Low: ECL (NRZ) mode
Float: CMI mode (input/output polarity inverted)
High: CMI mode (normal input/output)
[SPSL=1] Serial Clock:
Controls the timing of SDI and SDO.
[SPSL=0] Receive Monitor Mode Enable:
SCK_MON
CIS
CI
When high, adds 20dB of flat gain to the incoming signal before
equalization.
NOTE: Channel specific monitor modes can only be enabled through
the serial port. Rx Monitor Mode is only available in CMI mode
[SPSL=1] Serial Data Input:
Inputs mode and address information. Also inputs register data during
a Write operation. Both address and data are input least significant bit
first.
SDI_PAR
SDO_E4
94
93
[SPSL=0] Data Width Select:
Selects 4 bit parallel (input high) or serial mode (input low)
[SPSL=1] Serial Data Output:
Outputs register information during a Read operation. Data is output
COZ/
CI
least significant bit first
[SPSL=0] Rate Select:
Selects E4 operation (input high) or STM1/STS3 operation (input low)
POWER AND GROUND PINS
It is recommended that all supply pins be connected to a single power supply plane and all ground pins be
connected to a single ground plane.
NAME
PIN
TYPE DESCRIPTION
5, 12, 21, 74, 85, 92, 99, 105,
VCC
VDD
S
S
Power Supply
109, 116, 120, 126
23, 37, 40, 44, 48, 49, 53, 57, 60
CMOS Driver Supply
6, 13, 16, 22, 73, 82, 84, 91,
102, 108, 112, 113, 114, 115,
117, 123
GND
VSS
G
G
Ground
24, 36, 39, 43, 47, 50, 54, 58, 61
CMOS Driver Ground
20