Control Circuit; Power Supply Circuit Operation Outline - Epson Perfection 4870 Photo Service Manual

Perfection 4870 Photo

2.4 Control Circuit

2.4.1 Power Supply Circuit operation outline

The Control Circuit of this scanner consists of the following circuits.
Main Board
Table 2-3. IC Explanation
Location IC
IC1 A3957SLB-ATR
IC2 A3957SLB-ATR
IC3 AT93C46-10SI-1.8
IC4 UPC37M32
IC5 E01A23EB
IC6 MR27V402EJA
IC7 AS7C31025-15TJC
CCD Board
Table 2-4. IC Explanation
Location IC
IC1 ILX183K
IC2 BA178M05FP-E2
IC3 AD9826KRS-REEL
IC4 E02A41YA
TPU Main Board
Table 2-5. IC Explanation
Location IC
IC1 A3957SLB-ATR
IC2 A3957SLB-ATR
OPERATING PRINCIPLES
Location IC
IC8 ISP1581BD (GX)
IC9 K4S561632D-TC75000
IC10 74LVC138AD
IC11 S80927CLMCGGX
IC12 74LVC02AD
IC13 K4S561632D-TC75000
IC14 TSB43AA82APGE
Location IC
IC5 NJU7665CF-TE1
IC6 74HCT4053PW
IC7 74ACT244
IC8 74ACT244
Location IC
IC3 74HCT595
IC4 74HCT595
Control Circuit
SUB_C Board
Table 2-6. IC Explanation
Location IC
IC1 PSSI2021SAY
SUB_D Board
Table 2-7. IC Explanation
Location IC
IC1 PSSI2021SAY
SUB_A Board (Power Button)
Switch: PS-132-B22PBS
SUB_B Board (LED: Built in the Lid TPU)
LED: ON/OFF LED (blue)
Panel Board (Start Button)
Switch : EVQPEE04M
LED : READY LED (green)
ERROR LED (red)
Power supply
220-240V: MPW0709
Revision A
Location IC
IC2 PSS2021SAY
Location IC
IC2 PSS2021SAY
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