cx23881 Conexant Systems, Inc., cx23881 Datasheet - Page 3

• Manufacturer Part Number: cx23881
• Description: Pcl Audio/video Broadcast Decoder
• Manufacturer: Conexant Systems, Inc.

As a PCI initiator, the CX23880/CX23881 can take control
of the PCI bus to stream data as soon as the bus is available,
thereby avoiding the need for on-board frame buffers.
The CX23880/CX23881 contains a pixel data First In, First Out
(FIFO) to decouple the high-speed PCI bus from the continuous
video data stream. The video data input may be scaled, color
translated, and burst-transferred to a target location on a field
basis. This allows for simultaneous preview of one field and
capture of the other field. Alternatively, the CX23880/CX23881
is able to capture or preview both fields simultaneously.
The fields may be interlaced into memory or sent to
separate field buffers.
CX23880 block diagram
Video Input
Analog video signals are input to the CX23880/CX23881 via
a four-input multiplexer. The multiplexer can select between
four composite source inputs or between three composite and
a single s-video input source. When an s-video source is input
to the CX23880/CX23881, the luma component is fed through
the input analog multiplexer, and the chroma component
feeds directly into the C-input pin. An Automatic Gain Control
(AGC) circuit enables the CX23880/CX23881 to compensate
for non-standard amplitudes in the analog signal input.