G-6
ELECTRICAL DIAGRAMS
SQUARE WAVE TIG 275
Display Board Schematic (L10768)
N_GND
DISP3
2
1
4
9
5
10
7
6
8
3
N_GND
DISP1
2
1
4
9
5
10
7
6
8
3
1.00K
R57
14
3
Rx
Vdd
d
BANK1
g
DATA OUT
f
CLOCK
MC14489
DATA IN
h
Vss
BANK3
BANK4
BANK2
a
/ENABLE
e
c
BANK5
b
X8
18
9
17
6
5
2
10
19
8
1
13
12
16
20
11
15
4
7
DISP2
2
1
4
9
5
10
7
6
8
3
1000V
750p
C26
1N4007
D10
X7
1
2
3
D14
1000V
750p
C25
1N4007
D12
47.5K
R98
1N4007
D13
J20
8
3000V
.0047
C43
1N4007
D11
6.81K
R121
47.5K
R23
100K
R29
47.5K
R24
1.00M
R25
15.0K
R31
221K
R128
47.5K
R36
100V
100p
C53
47.5K
R22
100K
R26
100K
R30
44.2K
R37
X7
7
6
5
VOLT
GAIN = 4
GAIN = .042
1.00K
R39
10K
CW
R2
475K
R32
1.00M
R33
C46
47.5
R5
47.5
R4
47.5
R10
47.5
R8
47.5
R9
47.5
R6
CONTROL BD GND
L_GND
V_5V
+15V
+15V
+15V
L_GND
C47
X4
1
2
50V
0.1
C13
C2
J20
1
N_GND
Q2
2N4401
10.0K
R126
GND
IN
OUT
X2
CONTROL BD 15V
4.75K
R116
X4
11
10
X4
14
7
X4
9
8
D3
L_5V
Q1
2N4401
100V
100p
C45
X4
13
12
47.5K
R117
D4
47.5
R17
47.5
R13
D6
1.0
35V
C7
47.5
R19
47.5
R14
47.5
R15
26.7
R120
X12
9
10
8
X12
12
13
11
C8
ISOLATED CIRCUIT
47.5
R18
C11
1.0
35V
C12
GND
IN
OUT
X3
50V
0.1
C23
MC14489
Vss
Vdd
X8
3
14
MC14489
Vss
Vdd
X9
3
14
50V
0.1
C24
1N4936
D9
J20
2
1.0
35V
C16
1N4936
D8
1.0
35V
C15
TCF6000
X10
8
1
Q4
2N4403
N_GND
N_GND
L_5V
A_5V
L_GND
L_GND
L_5V
L_GND
L_GND
V_5V
A_5V
50V
0.1
C22
1.00K
R50
50V
0.1
C35
CUR_FB
X10
3
1.00K
R42
10.0K
R44
1.00K
R43
J20
5
15.0K
R46
X7
14
13
12
50V
0.1
C33
C30
332K
R112
X10
5
4.75K
R49
15.0K
R111
5K
CW
R1
1.00K
R47
10.0K
R41
J20
3
GAIN = 4
LO_CUR_FB
HI_CUR_FB
AMP
D16
X10
2
GAIN = .545
+15V
L_GND
N_GND
X7
8
9
10
100V
47p
C34
1.00K
R53
L_GND
1.00K
R51
X10
4
10.0K
R123
15.0K
R52
15.0K
R122
ELECT.
15.0K
R45
100V
47p
C32
J20
6
L_5V
L_GND
L_5V
L_5V
Q5
2N4401
X12
4
5
6
1.00K
R64
22.1K
R21
1N4936
D18
22.1K
R115
N_GND
4.75K
R124
C51
4.75K
R60
50V
0.1
C41
S-8054HN
Vdd
Vss
RES
X6
1.0
35V
C52
100V
22p
C40
X10
6
C42
J20
7
L_GND
50V
0.1
C38
100V
22p
C39
4.75K
R125
4.75K
R62
4.75K
R63
50V
0.1
C37
10.0K
R55
130
8.0MHz
Y1
L_5V
4.75K
R61
1W
5.1V
DZ1
10.0K
R56
L_5V
L_GND
L_5V
N_GND
X10
7
1.00M
R59
4.75K
R87
J20
4
4.75K
R127
119 KHz OSC.
/LINESYNC
OUTPUT_ENABLE
AC
X12
1
2
3
74HC373
X11
20
10
50V
0.1
C49
47.5
R11
10.0K
R38
D2
4.7
35V
C1
C9
100K
R20
26.7
R119
50V
820p
C14
D7
D5
47.5
R7
47.5
R16
C6
74HC132
X12
14
7
47.5
R12
1.0
35V
C10
Q3
2N4401
68HC11A1
X5
48
23
C17
50V
0.1
C48
27C256
X1
28
14
-Vsp
1.0
35V
C5
1.0
35V
C18
VOLTS
53
D-
SUPPLY
C-
LABELS
EARTH GROUND CONNECTION
R-
128
POWER SUPPLY SOURCE POINT
12
LAST NO. USED
X-
VOLTAGE NET
COMMON CONNECTION
DZ-
1
18
FRAME CONNECTION
-Vsp
WORK
20
10
OE
D1
Q5
Q6
LE
Q7
Q4
Q3
Q2
Q1
Q0
Vcc
GND
D7
D5
D3
D4
D0
D2
D6
74HC373
X11
8
13
2
5
9
15
18
12
1
19
7
14
11
16
17
3
6
4
48
23
XTAL
PA1
EXTAL
PE1
PD2
/XIRQ
VRL
/IRQ
IC1/PA2
/RESET
PD1
PD0
PA3
PA7
PE0
PE3
PE2
PD3
PD5
PD4
MODA
Vss
VRH
PA0
AD2
AD1
E
AD0
A11
A8
AD7
AD4
AD6
A14
A12
AD5
PA4
R/W
A10
A9
AS
PA5
A15
68HC11A1
MODB
AD3
PA6
A13
Vdd
X5
28
47
43
9
6
5
46
7
21
20
15
13
30
40
29
41
17
25
18
39
31
8
33
32
1
2
3
26
14
19
45
22
35
10
11
12
44
42
38
4
16
24
37
27
36
34
4.75K
R95
4.75K
R72
4.75K
R73
14
28
D4
A7
D0
D1
A1
GND
/CE
A12
A13
D7
A5
A14
/0E
A4
A3
D3
A2
A6
A11
A9
D6
A8
A10
D5
A0
Vpp
D2
Vcc
27C256
X1
16
15
20
12
27
7
11
22
26
10
17
9
1
21
24
2
3
19
23
25
5
13
6
18
8
4
X4
3
4
50V
0.1
C21
50V
0.1
C20
L_5V
L_GND
+15V
L_GND
+15V
+15V
N.A. SINCE COMPONENTS OR CIRCUITRY ON A PRINTED CIRCUIT BOARD MAY CHANGE
WITHOUT AFFECTING THE INTERCHANGEABILITY OF A COMPLETE BOARD, THIS DIAGRAM MAY
NOT SHOW THE EXACT COMPONENTS OR CIRCUITRY OF CONTROLS HAVING A COMMON CODE
50V
0.1
C19
50V
0.1
C50
GENERAL INFORMATION
.022/50V
ELECTRICAL SYMBOLS PER E1537
CAPACITORS =
MFD
(
UNLESS OTHERWISE SPECIFIED)
1A, 400V
FILENAME:l10768-1AB
RESISTORS = Ohms (
(UNLESS OTHERWISE SPECIFIED)
DIODES =
UNLESS OTHERWISE SPECIFIED)
1/4W
DISP4
2
1
4
9
5
10
7
6
8
3
4.75K
R75
AC
LO_CUR_FB
HI_CUR_FB
OUTPUT_ENABLE
LINESYNC
1.00K
R58
4.75K
R76
1N4936
D15
X4
5
6
33074A
X7
4
11
NOTES :
+15V
-Vsp
NUMBER.
475
R118
14
3
Rx
Vdd
d
BANK1
g
DATA OUT
f
CLOCK
MC14489
DATA IN
h
Vss
BANK3
BANK4
BANK2
a
/ENABLE
e
c
BANK5
b
X9
18
9
17
6
5
2
10
19
8
1
13
12
16
20
11
15
4
7
AMPS
DISP6
2
1
4
9
5
10
7
6
8
3
50V
0.1
C29
DISP5
2
1
4
9
5
10
7
6
8
3
L_GND
L_5V
LATCH
LO_VOLT_FB
CLOCK
DATA
HI_VOLT_FB
HI_VOLT_FB
LO_VOLT_FB
G-6
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NOTE: Lincoln Electric assumes no responsibility for liablilities resulting from board level troubleshooting. PC Board repairs will invalidate your factory warranty. Individual Printed Circuit Board Components are not
available from Lincoln Electric. This information is provided for reference only. Lincoln Electric discourages board level troubleshooting and repair since it may compromise the quality of the design and may result
in danger to the Machine Operator or Technician. Improper PC board repairs could result in damage to the machine.
L10768
7-24-98
