MT90870AG Zarlink, MT90870AG Datasheet - Page 40

• Manufacturer Part Number: MT90870AG
• Description: Switch Fabric 12K x 12K/8K x 4K 1.8V/3.3V 272-Pin BGA Tray
• Manufacturer: Zarlink

Specifications of MT90870AG

• Package: 272BGA
• Number Of Ports: 32
• Fabric Size: 12K x 12K|8K x 4K
• Switch Core: Non-Blocking|Blocking
• Port Speed: 2.048|4.096|8.192|16.384 Mbps
• Operating Supply Voltage: 1.8|3.3 V

4.2.3
The Backplane Output Enable Bit (BE) of the Backplane Connection Memory has direct per-channel control on the
high-impedance state of the Backplane Output streams, BSTo0-31 (for Non-32 MB/s Mode) and BSTo0-15 (for
32 Mb/s Mode). Programming the BE bit to a LOW state will set the stream output of the MT90870 to High
Impedance for the duration of the channel period. See Section 12.4, Backplane Connection Memory Bit
Definition, for programming details.
The BCSTo0-3 outputs remain active.
(32 Mb/s)
(32 Mb/s)
(32 Mb/s)
(32 Mb/s)
BCSTo0
BCSTo1
BCSTo2
BCSTo3
BSTo0
BSTo3
BORS Set HIGH
BSTo2
BSTo1
FP8o
C8o
Figure 15 - Backplane Port External High Impedance Control Timing (32 Mb/s Mode)
Channel 0
bits 7-0
Channel 0
bits 7-0
Channel 0
bits 7-0
Channel 0
bits 7-0
Channel 1
bits 7-0
Channel 1
bits 7-0
Channel 1
bits 7-0
Channel 1
bits 7-0
Zarlink Semiconductor Inc.
MT90870
40
Channel 510
bits 7-0
Channel 510
bits 7-0
Channel 510
bits 7-0
Channel 510
bits 7-0
One C16o cycle
Channel 511
bits 7-0
Channel 511
bits 7-0
Channel 511
bits 7-0
Channel 511
bits 7-0
Data Sheet