GS3140 Datasheet, PDF (21/40 Pages) Semtech Corporation – Multi-Rate Adaptive 3G SDI Equalizer

SDIN pin
Configuration and
Status Register
GSPI_LINK
_DISABLE
BUS_THROUGH
SDOUT pin
High-Z
CS pin
Figure 4-4: GSPI_LINK_DISABLE Operation
4.11.3.2 GSPI Bus-Through Operation
Using GSPI Bus-Through operation, the GS3140 can share a common PCB trace with
other GSPI devices for SDOUT output.
When configured for Bus-Through operation, by setting the
GSPI_BUS_THROUGH_ENABLE bit to 1, the SDOUT pin will be high-impedance when
the CS pin is HIGH.
When the CS pin is LOW, the SDOUT pin will be driven and will follow regular read and
write operation as described in Section 4.11.3.
Multiple chains of GS3140 devices can share a single SDOUT bus connection to host by
configuring the devices for Bus-Through operation. In such configuration, each chain
requires a separate Chip Select (CS).
SDIN pin
Configuration and
Status Register
GSPI_LINK
_DISABLE
BUS_THROUGH
SDOUT pin
High-Z
CS pin
Figure 4-5: GSPI_BUS_THROUGH_ENABLE Operation
Table 4-5: GSPI_BUS_THROUGH_ENABLE Bit Operation
Bit State
0
1
Description
Disables Bus-Through operation
Enables Bus-Through operation
When CS is HIGH, the SDOUT pin will be high impedance.
When CS is LOW, the SDOUT pin is driven.
GS3140
Final Data Sheet
PDS-060939
Rev.1
May 2015
www.semtech.com
21 of 40
Semtech
Proprietary & Confidential