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CR1 chassis (E)
10
No
Pin name
I/O
Level
PU/PD [kW]
Power supply
Functional description
for buffer
1
HDF
O
ANALOG
AVDD1/AGND1
Horizontal dynamic focus waveform
(R-strings DAC)
2
DCC2
O
ANALOG
AVDD1/AGND1
Center voltage of 8bit R-String DAC
4.
DA BOARD
4-1. GENERAL
The DA board comprises only the DSP IC inputs and outputs and relevant peripheral applications.
The pin functional description of DA board connector (CN502 on D board) as viewed from the set is substitutable with the D board
circuit description, and here, the DSP functions in the DA board are described.
Arrangement on A side of DA Board :
Vsaw Buffer
(IC1102)
CN1101
DSP
(IC1101)
4-2.
FUNCTION
The DA board provides mainly two functions:
(1) PLL function (alias "Jungle") that receives Hsync from the OSD IC (Sync Processor built in) and outputs HD stably synchronized
with Hsync
(2) DSP function that generates various deflection circuit control waveforms synchronized with Vsync and HFBP and outputs them by
DAC
The functions (1) and (2) are interacted, and the CLK to form waveforms by (2) is generated by (1). Accordingly, internal digital clock
is timing-locked to horizontal deflection.
Also, Vsaw (original waveform to output horizontal deflection) is outputted to the D board through active filter by an external buffer
(OP-AMP) to minimize the noise.
The deflection control waveforms outputted from DSP are classified into mainly three types depending on the kind of DAC.
PWM D/A type : DC only
1bit D/A type : V-period control waveforms, except Vsaw itself
Waveforms generated by filtering 0 V - 3.3 V 1/0 signals in RC. The D range is inevitably 0 V to 3.3 V.
R-Strings D/A : Mainly H-period waveforms. Vsaw belongs to this because of necessary
resolution.
Static DAC that outputs waveforms directly. The voltage range to generate waveforms is 1 V to 2 V. Some H-period waveforms
may be modulated at V-period.
For detailed DSP IC control by the micro controller, refer to the Software Specifications.
The following shows the pin assignment of DSP IC (extracted from NEC Specifications)
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