cxa2076q Sony Electronics, cxa2076q Datasheet - Page 33

• Manufacturer Part Number: cxa2076q
• Description: Y/c/rgb/d For Pal/ntsc Color Tvs
• Manufacturer: Sony Electronics

Description of Operation
1. Power-on sequence
The CXA2076Q does not have an internal power-on sequence. Therefore, power-on sequence is all controlled
by the set microcomputer (I
1) Power-on
The IC is reset and the RGB outputs are all blanked. Hdrive starts to oscillate, but oscillation is at the
maximum frequency (16kHz or more) and is not synchronized to the input signal. Output of vertical signal
VTIM starts, but Vdrive is DC output. Bus registers which are set by power-on reset are as follows.
2) Bus register data transfer
The register setting sequence differs according to the set sequence. Register settings for the following
sequence are shown as an example.
AGING
RON
GON
BON
PICON
VOFF
VFREQ
FHHI
HSIZESW
CD-MODE = 0: Automatic selection mode of the countdown mode
AKBOFF
Set sequence
Power-on
Degauss
VDRIVE oscillation
AKB operation start
AKB loop stable
Video output
= 0: All white output aging mode OFF
= 0: Rch video blanking ON
= 0: Gch video blanking ON
= 0: Bch video blanking ON
= 0: RGB all blanking ON
= 1: VDRIVE output stopped mode
= 0: Automatic identification mode (identification starts at 50Hz)
= 1: H oscillator maximum frequency mode
= 0: Normal
= 0: AKB mode
2
C bus controller).
CXA2076Q register settings
Reset status in 1) above.
Reset status in 1) above.
The CRT is degaussed in the completely darkened condition.
The IC is set to the power-on initial settings. (See the following page.)
A sawtooth wave is output to VDRIVE and the IC waits for the vertical
deflection to stabilize. The HDRIVE oscillator frequency goes to the standard
frequency.
PICON is set to 1 and a reference pulse is output from Rout, Gout and Bout.
Then, the IC waits for the cathode to warm up and the beam current to start
flowing.
Status register IKR is monitored.
IKR = 0: No cathode current
IKR = 1: Cathode current
Note that the time until IKR returns to 1 differs according to the initial status
of the cathode.
RON, GON and BON are set to 1 and the video signal is output from Rout,
Gout and Bout.
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CXA2076Q