Grass Valley 8920DMX - Manual (Page 28)

28 8920DMX Instruction Manual
Functional Description
Demultiplexer
The demultiplexer is a single chip solution for demultiplexing of digital
audio channels out of digital video signals. It supports the demultiplexing
of 20- or 24-bit synchronous audio data with a 48 kHz sample rate. The
demultiplexer supports video standards with rates from 143 Mb/s to 540
Mb/s.
Parallel to Serial Converter
The 8920DMX uses a standard 10-bit 270 Mbs Serializer.
CPU Embedded Processor
The embedded processor provides the interface between the user and all
the processing logic inside 8920DMX and communication between a host
processor and the 8920DMX.
The CPU contains:
• FLASH memory (stores data for FPGA programming
and configuration),
• Address decoder,
• Address Latch,
• Extended address register for FLASH memory,
• EEPROM (stores calibration and user setup data),
• Network interface, and
• ISP voltage regulator.
Power Supply
From the external source +12 V, the on-board supply provides +5 V, -5 V
and +3.3 V for the 8920DMX. The power supply uses a monolithic
switching power supply operating in Buck mode. Buck mode switching
regulators are used to generate a lower voltage from higher voltage input.
If the supply ever activates its protective crow bar diode, a high current will
be developed and the input fuse, F1 will blow.