© 2022
4
WTC3243 TEMPERATURE CONTROLLER
WTC3293 EVALUATION BOARD SCHEMATIC
VDD
1
VSET
2
LIMA
3
LIMB
4
P
5
+1V
6
I
7
SG
8
S+
9
BIAS
10
OUT
A
11
OUTB
12
GND
13
VS
14
U1 WTC3243
Q1
3904
Q2 3904
U2 2.5V
VDD
VDD
VDD
VDD
VDD
LED
GREEN
VDD
OUT
A
OUTB S+
+1V
P
I
VSET
LIMA
LIMB
BIAS
S-
VDD VS PGND
OUT
A
OUT
B
SENSOR-
LIM A
LIM B
P GAIN
I TERM
SET
T
SGND
0.00
2.5V
SET
T
COM
GND
1
PWR
2
P1
Power Jack
VDD
1mA
100uA
10uA
EXT
VSET
VDD
1 2 3
TB1
Input Connections
REN
ACT
T
1 2 3 4
TB4
Output Connection
2
3
1
8
4
U4A
LM393AD
6
5
7
8
4
U4B
LM393AD
1
2
3
Q3 PMBT3906
VS
D2 LM4040 2.5V
CU4 0.1uF
CU3 0.1UF
VDD
C4 0.1UF
VDD
D1
1N4148
+
C3 4.7 uF
+
C1 4.7 uF
+
C2 4.7 uF
VS
VDD
VS
VDD
VDD
CU5 0.1UF
VDD
R52 N/L
R53 N/L
R54 N/L
R55 N/L
Limit B: To set a Fixed Limit Remove R19 and load R53
Limit A: To set a Fixed Limit Remove R18 and load R52
P Gain: To set a Fixed P
Gain
Remove R8 and load R54
I TERM: To set a Fixed I
Term
Remove R13 and load R55
TP7
TP4
TP3
TP5
CW
W
CCW
R5
200K
TP6
C5
0.1UF
C6
0.1UF
R50 N/L
R51 N/L
Set T
:
To set a Fixed Set point V
oltage
Remove R47 & R48 and load R50 & R51 Refer to Datasheet for Equations
TP2
TP1
1
2
3
JP2
T X
2
1
3
S1
ENABLE
CW
W
CCW
R4
200K
C7 0.1UF
9
10
8
4
11
U5C
OP747ARU
5
6
7
4
11
U5B
OP747ARU
13
12
14
4
11
U3D
OP747ARU
2
3
1
4
11
U3A
OP747ARU
5
6
7
4
11
U3B
OP747ARU
9
10
8
4
11
U3C
OP747ARU
VSET
JUMPER
VDD
VDD
R47 0.00
R48 0.00
ST3
ST4
ON
S2
SW DIP-3 SMT
1
2
3
JP3 Gain
1 2 3
JP1
VS+VDD Jumper
Bias Selection
FAN+ FAN-
R23
100K
R26 100K
R28
1.0K
R16
10.0K
R27
1.0K
R31
1.0K
R33 10.0K
R32
10.2K
R34
1.0K
R35
10.2K
R7
10.0K
R36 10.0K
R15
90.9K
R25 9.76K
R24 10.0K
3.3V
R29 287
R14 287
LIMB
LIMA
R13 0.00
R8 0.00
R10 10.0K
R17 10.0K
R9
10.0K
R19 1.50K
R18 1.50K
VDD
R21
20K
R22
2K
R20
200K
R30
20K
R
11
10.0K
R6 10.0K
1
2
3
4
5
6
TB2
TB6
1
2
3
4
5
6
TB3
TB6
COM
HVSET
CW
CCW
R1
5k
CW
CCW
R2
5k
CW
CCW
R3
5k
ST1
ST2
I2
I1
P2
P1
LB2
LB1
LA1
LA2
RSET
x10
x1
2
1
DAQ
FAILSAFE
PROTECTION
CIRCUIT