Toshiba 4560 Service Manual page 53

5.4.2 LED display circuit
(1) LED display method
For example, the following shows how the LED LP12 (APS) lights up for displaying "automatic paper
sensing".
DSPON0
When DSPON0 signal becomes "L" level, transistor Q3 is turned ON. Further, when IC1 pin16 (D8)
becomes "L " level, current flows from +5VD to LP6 (APS) through the transistor. In this way LP6
(APS) lights up.
Nov. 1997 © TOSHIBA
+5VD
R60
Current
R61
R
"L"
Q3
(APS)
LP6
5 - 9
"L" 16
D8
R17
IC1
4560/4570 DISPLAY