Matrix Circuits And Signal - Loewe Q2500B Serviceanleitung

Technology of Q 2500 colour TV set
- RGB driver stages
- Beam current limiter circuit
- Automatic cut off control
- I²C bus interface and control register
- DAC for programmable d.c. voltage
− PLL for generation of cycle frequency
− Control block for the synchronisation of the
output stages
− DAC for O/W, V control and H output stage
− Beam current dependent correction of the
vertical and horizontal amplitude and beam
current dependent H phase correction.
− Horizontal start up control
Document Q 2500
− I²C bus interface

4.7.1 Matrix circuits and signal

selection
The R-Y, B-Y and the Y signals are fed to the
IC via pins 26, 27 and 28. The green compo-
nent is recovered and the RGB signals pro-
duced using two matrix circuits, one after the
other.
These RGB signals are fed to a selection cir-
cuit, to which the RGB signals from the CCU
via pins 2, 3 and 4 and from the VGA-interface
via pins 35, 36 and 137 are also fed. With this
circuit the required signal is selected or two
signals mixed together.
103 © Loewe ProCollege