TEC B-443, Service Manual

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November, 99 All Rights Reserved 25
B-443 Bar Code Printer
Service Manual
3.10 Stepping Motor And DC Motor Driver/ Protection Circuit
MB
1
T
2
VMM
3
GND
4
VCC
6
I1
7
PHASE
8
I0
9
C
10
VR
11
MA
15
E
16
VMM
,14
GNDGNDGND
U17
PBL3770A
MB
1
T
2
VMM
3
GND
4
VCC
6
I1
7
PHASE
8
I0
9
C
10
VR
11
MA
15
E
16
VMM
,14
GNDGNDGND
U18
PBL3770A
C55
820p
C56
820p
C57
820p
C58
820p
R51
56K
R45
1K
R52
56K
R46
1K
R14
1 R15
1
R16
1
R17
1
PHASE1
PHASE2
VCC
VCC
VDD
VDD
L18
BEAD
L20
BEAD
C52
470u
C54
470u
C27
0.1u
C28
0.1u
MB
1
T
2
VMM
3
GND
4
VCC
6
I1
7
PHASE
8
I0
9
C
10
VR
11
MA
15
E
16
VMM
,14
GNDGNDGND
U19
PBL3770A
C59
820p
C60
820p
R53
56K
R47
1K
R18
1
R19
1
VCC
VDD
L19 BEAD
C53
470u
C29
0.1u
PHASE3
DCMA
DCMB
Q6
TIF32C
R54
68
R55
390
VDD
D5
IN4002
CTSENS
R23
10K
VCC
A
9
B
10
CLR
11
Q
12
Q
5
Cext
6
RCext
7
U12B
74HC123
R40
150K
/RESET
VCC
1 16
9
GND
8
U20A
2003
2 15
9
GND
8
U20B
2003
3 14
9
GND
8
U20C
2003
4 13
9
GND
8
U20D
2003
DIGITAL GND
MOTOR_GND
MOTOR_GND
MOTOR_GND
MOTOR_GND
MOTOR_GND
MOTOR_GND
D12
1N4002
D13
1N4002
D14
1N4002
D15
1N4002
I1
I0
DCM
CUTTER
A
1
B
2
CLR
3
Q
4
Q
13
Cext
14
RCext
15
U13A
74HC123
C12
10u
R41
150K
VCC
MOTOR
DIGITAL GND
1
2
3
4
5
6
RN6
10K 6PIN
¸Á»ï¾¹
1A1
2
1A2
4
1A3
6
1A4
8
2A1
11
2A2
13
2A3
15
2A4
17
1Y1
18
1Y2
16
1Y3
14
1Y4
12
2Y1
9
2Y2
7
2Y3
5
2Y4
3
1G
1
2G
19
U6
74LS244
C30
10u\TANT
1
2
3
4
5
6
7
JP3
CUTTER&PEEL
DIGITAL_GND
PEEL
VCC
DIGITAL GND
MOTOR_GND
1
2
3
4
JP12
STEP MOTOR
L31 BEAD
L30 BEAD
L29 BEAD
L28 BEAD
L27
BEAD
L7
BEAD
C78
0.01uF
C77
0.01uF
C73
0.01u
C74
0.01u
C76
0.01u
C75
0.01u
F2
FUSE2
F1
FUSE2
F3
FUSE2
D16
DSP
D17
DSP
MOTOR_GND
13,12,5
13,12,5
13,12,6
BUZZER
VCC
Fig. 3.11 Stepping Motor And DC Motor Driver/ Protection Circuit
This is the Stepping Motor and DC Motor Drive/ Protection Circuit. Connector JP12 sends the
pattern as shown in table1. The status of I0 & I1 determines the stepping motor power level, the
power level pattern is as shown in table2. Motor port is the protection pin. When it is at ‘ LOW’
level, the power of the motor system will be closed. Power will be ON again when MOTOR pin is
the pulse of ‘ HIGH’ level. PHASE1 and PHASE2 determine the pattern of stepping motor drive
circuit. For example, the sequence of PHASE1/PHASE2 in full step mode is 0/0
-> 0/1 ->
1/1 -> 1/0.
Step
Pin on JP12
1 2 3 4 PHASE
1 ON ON ON A
2 ON ON /A
3 ON ON ON /B
4 ON ON B
Table1 Stepping Motor Pattern
MOTOR CURRENT I0 I1
HIGH LEVEL 100% L L
MEDIUM LEVEL 60% H L
LOW LEVEL 20% L H
ZERO CURRENT 0% H H
Table2 Stepping motor power pattern
The power of DC motor is on when DCM pin is at ’ LOW’ level. PHASE3 determines the DC
motor rotation direction (forward or backward).