Toshiba e-STUDIO520 Service Manual page 415

9) Analog multiplexer circuit
This is a circuit to connect to COM with one of the four analog input signals. As following table
shows, the digital signals input into IC7-11 pin (A), IC7-10 pin (B) and IC7-9 pin (C) switch the corre-
sponding channels and IC7-3 pin (COM) at a high speed, and they are input into the A-D input termi-
nal of CPU. Each channel signal is an analog output signal of the reflective sensor and used to
adjust the sensor automatically.
C B A Corresponding channel
L L L
L L H
L H L
L H H
March 2005 © TOSHIBA TEC
Fig.16-102
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e-STUDIO520/600/720/850 REVERSING AUTOMATIC DOCUMENT FEEDER (RADF)
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