Epson LQ-570 Service Manual page 24

REV.-A
2.3.3
Sensor Circuits
Figure 2-21 shows thesensorcircuits block diagram. Detection of any excessive printheadtemperature
causes the TEMP2 signal to be sent directly to the CPU. Other signals, such as the CRHOME signal,
pass through the each low path filters before reaching the CPU. Terminals P50 to P55 on the CPU
are used for the ND mnvertor. The Vref circuit generates the A/D mnverior reference voltage Vref.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
,: Sensor Circuit
'
LEVER
GAP
Power On
I
I
THLD
Figure 2-20. /F?ESET Signal Timing
+5
6.2K
- - - . - - - - - -
Figure 2-21. Sensor Circuit Block Diagram
Printhead
'
1
0 . 0 2 2 ;
T
- - - - - - - - - - - - - - - - --1
r
Head Drive Voltage
2-16
u
LEVER
,
GAP
'E-1
-. . . . . . . . .
: