Epson PowerLite 5000, Service Manual

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EPSON PowerLite 5000 Service Manual
2-7
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An interlock switch is included for safety. The interlock switch shuts off the supply of
AC power if the lamp cover at the bottom of the main chassis is open.
•
The safety switch input signal stops power output to the light source lamp if the
projector detects overheating. The safety switch is mounted on the light guide unit
attached to the lamp inner housing.
Functional Outline
•
The interlock switch at the bottom of the main chassis shuts off power when the lamp
cover is opened. It is normally at the ON position.
•
The power supply cable is connected to CN800 on the main board. The following items
are also connected to CN800:
DC output line
PWDS signal for the power on/off control
Lamp power on/off control signal (LPSTC)
Background power (+3.3 V) on/off signal (BACTA)
Caution:
If the AC power cable is still connected after the power is shut off, +3.3 V background
voltage is supplied to the main board via CN800 and power on/off circuit.
•
The filter/rectification circuit reduces noise on the AC line and generates DC voltage for
the regulator.
•
The regulator generates the various DC voltage levels shown in the table below for the
switching regulator. The regulator detects the voltage output level at the +5 V line and
feeds the information back to the switching circuit to maintain a stable output level
regardless of load variations. Not every output voltage level is subject to adjustment.
Table 2-2 Output Specifications
Power Source +5 V +3.3 V +12 V +12 FV +22 V
Output voltage accuracy
(%)
±±
5
±±
5
±±
5 12.0-13.8 V 19.0-24.0 V
Ripple (mV p-p) 200 100 100 400 400
Ripple/Spike (mV p-p) 200 100 100 400 400
Output current Min (A) 1.0 0.3 0.2 0.05 0.0
Rated (A) 2.4 2.0 1.0 1.5 0.3
Peak(A) - - - 2.0 -
Overvoltage protection +7 V +4.6 V - +16 V +30 V
Overcurrent protection Transient
(Note)
Distortion Distortion Transient
(Note)
Transient
(Note)
Use Logic circuit Logic circuit Analog
circuit Fan/Audio
circuit Light valves
NOTE : Protection is the transient detection type, it is recoverable with power on.