Epson 900N, Service Manual

Page: 54 / 201

EPSON Stylus COLOR 900/900N Chapter 2 Operating Principles
49
2.3.4.2 Sensor Circuits
The printer’s sensors detect temperature and the mechanical status of
the printer. The CPU receives the temperature feedback, while two
ASICs receive the mechanical feedback: E05B59 (IC2) and E05B60
(IC3).
Temperature Feedback
The temperature feedback circuit includes three thermistors as well as
the temperature sensing circuitry in the nozzle selector inside the
printhead. Their functions are explained on the following page.
Figure 2-15. Temperature Sensor Support Circuitry
A N O D E 5
C N 8
C N 9
T h e r m i s t o r
N o z z l e
S e l e c t o r
4
H D 6 4 F 2 3 5 7 ( I C 1 )
T h e r m i s t o r o n t h e h e a t
s i n k o n t h e m a i n b o a r d
T h e r m i s t o r o n t h e m a i n b o a r d
A N 7
A N 6
A N 5
A N 4
A N 3
A N 2
A N 1
A N 0
1 1 2
1 1 1
1 1 0
1 0 9
1 0 8
1 0 7
1 0 6
1 0 5 1 9
2 1
2 0
1
2
9
1 0
H D S A M I
H P D S A M I
T H M
A N O D E 1
A N O D E 2
A N O D E 3
A N O D E 4
N o z z l e R o w s
R o w A
R o w C
R o w D
R o w E
R o w B