JVC 250 service manual Diagrams, Command ON Timing

Chapter 7---Troubleshooting

7.3 Diagrams

Command ON Timing

Figure 7-10POWER ON and POWER OFF command timing diagram.

When the AC Circuit Breaker is powered ON, the Low Voltage Power Supply generates a +5.1 V Standby voltage that goes to the System Controller PCB to power the CPU and IR Detectors. The Low Voltage Power Supply also puts out the +24 V Standby voltage (/FAN_ENA goes low) that provides power to the cooling fans. The cooling fans run from the time the AC Circuit Breaker is powered ON until approximately ten minutes after the projector receives a power Off command (AC Circuit Breaker still on).

When the projector receives a power ON command from the IR Remote, PC or Laptop, the System Controller PCB receives a /LAMP_OK from the Arc Lamp Power Supply. The System Controller PCB then drives the /LAMP_ENA signal

7-12 Model 250 Service Manual