Miranda NV5100MC Master Control, Справочное руководство

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34 Rev 2.10 • 17 Feb 11
3. Frames
Input (and Output) Cards
Figure 3-9 shows the synchronous AES signal path:
Figure 3 -9. Synchronous AES Signal Flow
Synchronous AES Input Backplanes
The IO5000-AES-IN-TP backplane module has 16 Phoenix connectors for balanced signals. The
IO5000-AES-IN-BNC backplane module has 16 BNC (75
Ω
) connectors for unbalanced signals.
(
Asynchronous AES input cards exist but are not used under master control.)
Analog Video Conversion
The EM0432 Analog Video Conversion (AVC) input module converts incoming composite analog
video signals (NTSC or PAL) to SD video.
Analog Video Conversion Input Module
Each of the 16 composite video inputs from the passive backplane module is received by a differen-
tial input amplifier. The single-ended outputs of these amplifiers are passed to anti-aliasing filters
before being processed by a video converter. The outputs of the converters are then passed to an
FPGA which serves as an SMPTE 259M formatter and bus driver. A PLL locked to the video con-
verter reduces jitter in the data formatting process. The outputs of the drivers feed the differential
traces on the motherboard.
S
The SD output of the AVC input module is line-locked to the incoming composite signal.
S
The input processing delays the signal by approximately 1.25 lines. Frame sync and subcarrier
phase alignment are not maintained with respect to reference. AVC modules are intended to
provide an economical way to convert signals to feed to monitors with SD or NTSC/PAL inputs
and for use in similar applications where signal timing is not critical.
Figure 3-10 shows a simplified view of the signal flow through the AVC input card.
Figure 3 -10. AVC Signal Flow
Analog Video Input Backplane
The AVC card uses the IO5000-AVC-IN backplane. It has 16 BNC connectors.
SD Video
SD Video Backplane and Input Module (EM0383)
The backplane applies SD video signals to a cable equalization circuit through a return loss com-
pensation network. The equalizer automatically compensates for up to 300m of Belden 1694A or
equivalent cable. The equalizer also has a muting function that prevents digital noise in the output
Bus
Tx
Backp la ne Motherb oard
Rx
Retime &
Format Data
Sync AES In
EM0432
Anti-
Alias Filter
Video
Decoder
SMPTE 259M-C Data
Formatter and LVDS Bus
Driver (×16)
Rx
Analog
Video
In
SD Video
(at motherboard)