Epson LX-810 Technical Manual

REV.-A
Reference Voltage Generation Circuit
Figure 2-32 shows the reference voltage generation circuit and Table 2-3 shows the reference voltage.
The reference voltage generation circuit is shown in Figure 2-32, the reference voltages are shown in
Table 2-3. The SLA7020M drives the stepping motor based on current proportional to the reference
voltages set here. There are four stages of reference voltage values (motor drive current values), and
these are switched to correspond to the drive speed of the motor.
+5V
CPU
LLPD78 10HG
(2 c ) ~A3
4 q,y
5
R53 6.8K
PA4 v
A
Vvv
6
R51 6.8K
PA5
n
Figure 2-32. Reference Voltage Generation Circuit
Table 2-3. Reference Voltage
PA5 I PA4 I PA3 I Reference Voltage
H]
H\Ll
0.634 V
H
I
L
I
H
I
0.359 v
L
I
H
I
HI 0.280 V
H
H
H
0.089 V
Z R47
* 5.49K
1%
~ Vref
E R46
“ 100
1%
7
,,.
2-28

Epson LX-810 Specifications

General

Print Method	Impact dot matrix
Number of Pins	9
Character Sets	96 characters (USASCII)
Line Spacing	1/6 inch
Paper Path	Rear
Interface	Centronics parallel
Noise Level	55 dB (A)