JVC 250, Service Manual

Page: 84 / 190

Chapter 5---Electronics
Model 250 Service Manual 5-29
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Convergence output amplifiers for all colors and both horizontal and
vertical axes
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Convergence enable and raster fill function
!
ILA
®
assembly driver circuitry with temperature compensation
!
Phase locked loop for ILA
®
assembly drivers
!
IIC serial bus interface
Convergence Deflection PCB - Inputs
X_RGB_CONV - x-axis Convergence waveform from the System Controller
PCB (the amplitude for full-scale correction is about 1 Vpp).
Y_RGB_CONV - y-axis Convergence waveform from the System Controller
PCB (the amplitude for full-scale correction is about 1 Vpp).
CORR_SYNC - square wave from the System Controller PCB, logic level
synchronization signal for the horizontal axis.
V_DRIVE - square wave from the Raster Timing Generator PCB, logic level
synchronized to vertical sync with four horizontal line duty cycle.
WIDTH_CONTROL - a DC waveform from the Horizontal Vertical Deflection
PCB that controls the image width.
IIC_CLK - IIC clock line.
IIC_DATA - IIC data line.
IIC_SINT - IIC interrupt line.
±15 V - input power from the Low Voltage Power Supply for the analog circuitry.
+5.1 V- input power from the Low Voltage Power Supply for the digital circuitry.
Convergence Deflection PCB - Outputs
RGB_ILA
®
(pos) - positive outputs to the ILA
®
for the red, green, and blue ILA
®
driver circuitry (about ±12 Vpp).
RGB_ILA
®
(neg) - negative outputs to the ILA
®
for the red, green, and blue ILA
®
driver circuitry (about ±12 Vpp).
H_PARABOLA - horizontal parabola for dynamic focus section of the High
Voltage Power Supply.
V_PARABOLA - vertical parabola for dynamic focus section of the High Voltage
Power Supply.
V_RAMP - vertical ramp waveform to the Horizontal Vertical Deflection PCB
(about 4 Vpp).
V_PARABOLA - vertical parabola waveform to the Horizontal Vertical
Deflection PCB (about 4 Vpp).