Mitsubishi Electronics WS-48613, WS-65513, WS-48513, WS-55513 manual Short Detect, RAY Protect

SHORT Detect

The short Detect circuitry is shown in Figure 4-6and is the same as in the V19 and V21 chassis. If a short occurs in the + or – 24V supplies, pin 46 on IC7A00 goes Low indicating a short and the TV shuts Off. With -24V shorted, the 12VS supply turns Q9A53 On, pull- ing the SHORT line Low. If +24V is shorted D9A54 is forward biased and the short line goes Low.

X-RAY Protect

Refer to Figure 4-7, the X-Ray input is at pin 47 of IC7A00, and is normally High. The X-Ray Protect circuit monitors:

•Excessive HV

•Excess CRT Beam Current

•Excess HV circuit Current

If any of the preceeding occurs, the X-Ray line goes Low, and the TV shuts Off.

The monitoring circuits for X-ray Protect are described in the detail in the Deflection and HV Section. Other parallel inputs to the µPC, are listed in Table 4-1.

IC7A00 Additional Inputs

Pin #	Name	Source
6	SD-SUB	Sub Tuner Sync Detector
7	SD-MAIN	Main Tuner Sync Detector
62	H-SYNC-IN	ASIC Horizontal Sync
64	V-SYNC-IN	ASIC Vertical Sync
92	AFT1	Main Tuner AFT voltage.
93	AFT2	Sub Tuner AFT voltage
94	VBLK	Deflection Loss Detect circuit
97	CV-IN-SUB	Sub Video (CCD, V-chip,etc)
100	CV-IN-MAIN	Main Video (CCD, V-chip,etc)

Table 4-1: µPC Inputs

4-6