Rev. B
Mechanism Configuration and Operating Principles
TM-U200D/U200PD Technical Manual
Printer Mechanism Drive Circuit
Print head drive circuit
The head drive signal is output from CPU (U5) pin 64 to 72. Receiving this drive signal, the
transistor array (QM1, QM2) and transistor array (QM3) turn On, Off, and drive the head.
Power supply time to the head is adjusted by the supplied power voltage. CPU (U5) changes the
power voltage between analog and digital at AN0 (pin 7) and decides and controls the head
power supply time according to the internal time table.
In order to prevent damage to the head during excessive printing, a heat Detector has been
installed in the print head. An analog-digital conversion of the partial pressure difference
between the heat Detector and R18 is carried out in AN1 (PIN8) of the CPU (U5) and the
temperature is calculated. If the head is overheating or working improperly, the ERROR LED
flashes.
Figure 2-24 Print head drive circuit
Print head unit
COM (# 3.5.7 )
# 5
# 7
# 1
# 3
w b h
j b g
HEAD1
HEAD5
HEAD6
HEAD2
RM3
8
7
6
5
4
3
2
1
Q4
9
7
5
3
8
6
4
2
1
1
0
QM1
Q6
Q5
Q7
+5V
RM4
8
7
6
5
4
3
2
1
Q8
9
7
5
3
8
6
4
2
1
1
0
QM2
Q10
Q9
Q11
HEAD3
HEAD7
HEAD9
HEAD8
+24A
D7
68
69
65
72
Q12
R20
1
2
3
CN7
4
5
6
7
8
9
10
11
12
13
14
15
P44
P45
P41
P50
HEAD4
67
66
70
P43
P42
P46
71
P47
64
P40
8 HD TEMP
P61/AN1
7 V DTC
P60/ANO
6
AVSS
5
AVCC
C30
C31
R45
R46
R18
C19
C29
R8
+
C33
_
R19
+24DT
# 9
C0M ( # 1.2.9 )
THEM1
THEM2
# 4
# 6
# 8
COM (# 4.6.8 )
# 2
FG
D27
D28
Q13
U5
+5V
+5V
D50
D32
D38
D39
D40
D41
D42
D43
D45
D44
Summary of Contents for TM U200D - B/W Dot-matrix Printer
Page 2: ...technical manual TM U200D U200PD EPSON English 4005680 ...
Page 4: ...EPSON SEIKO EPSON CORPORATION Printed in Japan E9608130 0000SE ...
Page 145: ...Rev B Disassembly Assembly and Adjustment 5 49 TM U200D U200PD Technical Manual ...
Page 146: ...5 50 Disassembly Assembly and Adjustment Rev B ...
Page 147: ...Rev B Disassembly Assembly and Adjustment 5 51 TM U200D U200PD Technical Manual ...
Page 148: ...5 52 Disassembly Assembly and Adjustment Rev B ...
Page 154: ...Appendix A 6 Rev B Main Circuit Board A Parts Layout ...
Page 155: ...Rev B Appendix A 7 TM U200D U200PD Technical Manual Main Circuit Board C Parts Layout ...
Page 156: ...Appendix A 8 Rev B RS 232 Serial Interface Circuit Board Parts Layout ...
Page 169: ...Rev B A 21 TM U200D U200PD Technical Manual Case Unit Lubrication Points Diagram ...