External Sync Circuit; Dc Servo Circuit; Motor Drive Circuit; Character Generator Circuit - Sony SSC-DC593 Service Manual

2-2-4. External Sync Circuit

This camera is compatible with VS synchronization and MPX-VD synchronization (SSC-DC690) or LL
synchronization (SSC-DC593/593P/598P).
VS: The sync source VS signal from pin 13 of CN203 is clamped using IC205 and then input to
pin 34 of IC204 so as to constitute VReset/H-PLL. The H-phase comparison output signal at
pin 23 of IC204 is passed through a low-pass filter (LPF) around IC503 and reflected on
internal master LC-type VCO (around IC508). Synchronization is detected using IC204.
LL: The V pulse (power frequency sync pulse) from pin 13 of CN203 is input to pin 35 of IC204
and V-reset inside IC. The V pulse and an internal VD pulse constitute PLL. The V-phase
comparison output signal (at pin 23 of IC204) is passed through a low-pass filter around
IC503 and reflected on internal master LC-type VCO (around IC508).
MPX-VD: The sync source VD signal separated from the superimposition line in a DC-DC converter is
obtained from pin 13 of CN203. After the signal is waveform-shaped around IC210, it is
input to pin 35 of IC204 and V-reset inside IC. The V pulse and an internal VD pulse
constitute PLL. The V-phase comparison output signal (at pin 23 of IC204) is passed through
a low-pass filter around IC503 and reflected on internal master VCXO (around IC504).

2-2-5. DC Servo Circuit

The DC servo circuit controls the drive signal (at pin 1 of IC402) for auto iris lens driving from a
microcomputer (IC304) through EVR (IC301).

2-2-6. Motor Drive Circuit

The motor drive circuit controls a stepping motor-driven driver (IC309) from microcomputer IC304 so as
to switch the infrared cut-off filter and glass placed in front of CCD.

2-2-7. Character Generator Circuit

The character generator circuit controls character signal B (IC307) for menu display from microcomputer
IC304.
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SSC-DC593/DC593P/DC598P (E)