Impedance Matching (S Caps) - Sony CPD-420GS Training Manual

Impedance Matching (S CAPS)

The Micro IC1001 (N Board) controls the Impedance Matching (S CAPS)
circuit to match the Timing and Sync parameters of the video inputs. The
S CAPS are utilized to switch different capacitors into the horizontal de-
flection yoke, thus changing the impedance. IC1001 pin 46 S5, pin 47
S4, pin 48 S3, pin 49 S2, pin 50 S1 and pin 53 S0 control the S CAP
circuits comprised of circuit elements Q508, Q509, Q510, Q511, Q512,
Q513 and associated components respectively. IC1001 outputs a H (+5V)
to switch the respective S CAP into the circuit.
Note: With No Video Input, the H freq. Is 69.696kHz and the S Cap logic
outputs are all +5V.
640 X 480
S CAP Switching
S0 H
Q513 +5V
S1 H
Q512 +5V
S2 L
Q511 0V
S3 H
Q510 +5V
S4 H
Q509 +5V
S5 L
Q508 0V
H Freq. 43.284 kHz
Picture resolutions were generated using Windows 95 "Display Properties" for the CPD-420GS.
Resolution (Dots x Lines)
800 X 600 1024 X 768 1152 X 864
H H
+5V +5V
H H
+5V +5V
H H
+5V +5V
H L
+5V 0V
L L
0V 0V
L L
0V 0V
53.545 kHz 68.740 kHz 67.523 kHz
71
S CAP Tables
Micro IC1001
Pin
53
Pin
50
Pin
49
Pin
48
Pin
47
Pin
46
N Board
1280 X 1024
H L
+5V 0V
H H
+5V +5V
H L
+5V 0V
L L
0V 0V
L L
0V 0V
L L
0V 0V
90.894 kHz
S CAP Switching No Sync Input
S0
Q513 +5V
S1
Q512 +5V
S2
Q511 +5V
S3
Q510 +5V
S4
Q509 +5V
S5
Q508 +5V
H Freq. 69.696 kHz
1600 X 1200
H
+5V
L
0V
H
+5V
L
0V
L
0V
L
0V
74.268 kHz
DOS Prompt
H H
+5V
H H
+5V
H H
+5V
H L
0V
H H
+5V
H H
+5V
31.496 kHz