3-16
3.4 THERMAL HEAD
The thermal head consists of heat elements and a thermal head driver that drives and controls the heat
elements.
When printing data is input from DI, print is "High" and non-print is "Low".
The data from the DI is transferred to the shift register at the rising edge of the CLK signal.
The data is stored into the latch register by making /LAT signal "Low" after one line data is transferred. The
heat elements are activated by making DST signal "High" in accordance with the stored print data.
In this printer, a division printing by 6 blocks is available. Each block has 64 dots heat elements.
3.4.1 Structure of the Thermal Head
Figure 3-7 shows the thermal head block diagram the printer.
Table 3-12 show the relationship between DST and activated heat elements.
D I
C L K
/L A T
D S T 6
D S T 5
D S T 2
D S T 1
V d d
G N D
V p
Shift Register
LAT Register
Output Driver
Heating Element
D
O
T
3 8 4
D
O
T
3 2 1
D
O
T
3 2 0
D
O
T
2 5 7
D
O
T
2 5 6
D
O
T
1 2 9
D
O
T
1 2 8
D
O
T
6 5
D
O
T
6 4
D
O
T
1
Block6
Block5
Blcok2
Block1
T H
Thermistor
T H
Heat Element
Out put Driver
/LAT Register
Shift Register
Figure 3-7 Thermal Head Block Diagram
