Epson TM-H6000 Service Manual page 155

Confidential
Thermal Head Drive Circuit
Printing is performed by applying voltage to the heating element resistor in the thermal head.
The GA (U30) controls all data transfers to the thermal head, and also controls the energizing
pulse. Firmware gives instructions to the GA, but data transfers and drive pulses are performed
automatically by the GA. Due to the circuit configuration, the six signal lines on the left side (all
controlled by GA) perform data transfers.
TH_STB1
TH_STB2
TH_LAT
TH_THERM
TH_D1
TH_D2
TH_SCLK
Appendix D-64 Product Overview
24VA
D36 R126
R127
R128
C67
D38
VCC
R129 R130
R131
R132
R135
R140
C79
C80
VCC
R121
R122
R120
L4
L5
L6
L7 L8 VCC
C66
C61
C69
C68
C73
C72
VCC
L9
U20
1 8
2 7
3 6
4 5
C76
L10
C81
U21
L11
Figure D-63
R123
R124
R125
CN22
VH
21
VH
20
C58
VH
19
/LAT
18
VDD
17
/STB1
16
TM1
15
GND
14
GND
13
GND
12
GND
11
GND
10
GND
9
TM2
8
/STB2
7
CLK
6
DI2
5
DI1
4
VH_1
3
VH_1
2
VH_1
1
R134
R143
R145
2
C82 C83 C84
C60
C59
Rev. A