3. Detailed Description
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Functional Overview
Serial Digital Input
Clock and Data Recovery
Serial-To-Parallel Conversion
Modes Of Operation
SMPTE Functionality
DVB-ASI Functionality
Data-Through Functionality
Additional Processing Features
Internal FIFO Operation
Parallel Data Outputs
Programmable Multi-Function Outputs
GS9090B Low-latency Mode
GSPI Host Interface
JTAG Operation
Device Power Up
3.1 Functional Overview
The GS9090B is a 270Mb/s reclocking deserializer with an internal FIFO and
programmable multi-function output port. The device has two basic modes of operation.
In Auto mode, the GS9090B can automatically detect SMPTE data streams at its input. In
Manual mode, the device can be set to process SMPTE or DVB/ASI data streams.
The digital signal processing core handles ancillary data detection/indication, error
detection and handling (EDH), SMPTE352M extraction, and automatic video standards
detection. These features are all enabled by default, but may be individually disabled via
internal registers accessible through the GSPI host interface.
The provided programmable multi-function output pins may be configured to output
various status signals including H, V, and F timing, ancillary data detection, EDH
detection, and a FIFO load pulse. The internal FIFO supports 4 modes of operation,
which may be used for data alignment, data delay, MPEG packet extraction, or ancillary
data extraction.
The GS9090B contains a JTAG interface for boundary scan test implementations.
3.2 Serial Digital Input
The GS9090B contains a current mode differential serial digital input buffer. The input
buffer has internal 50Ω termination resistors, which are connected to ground via the
TERM pin.
If the input signal is AC coupled to the device, the signal source common mode level will
be set internally to typically 1.45V. If the input signal is DC coupled to the device, the
internal biasing will be ignored. Please see AC Electrical Characteristics for Common
Mode range and swing characteristics.
GS9090B GenLINX® III 270Mb/s Deserializer for SDI
Data Sheet
22 of 72
40749 - 5
May 2010
GENNUM [ GENNUM CORPORATION ]
