© 2022
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WTC32ND TEMPERATURE CONTROLLER
CONFIGURE THE JUMPERS & SWITCH
On the underside of the WTC32ND-EV Evaluation Board
you will find the jumpers and switches. Use
below
to locate them.
Figure 5. Bottom View, Jumper Locations -- Factory Default
SET THE POWER SELECT JUMPER
V
S
drives the output stage while V
DD
powers the
control electronics.
shows the jumper location and
shows the jumper position. The factory default is
to separate the V
S
and V
DD
power supply inputs.
• To use Single Supply Operation, place the jumper in the
V
S
+ V
DD
or “1” position. Note that when in this position,
V
S
on the input terminal block pin will be at the same
potential as the V
DD
pin.
• To use Dual (separate) Supply Operation, place the
jumper in the V
DD
or “2” position.
1
V
S
+ V
DD
2
Dual (separate) Supply Operation
Factory Default
1
V
S
+ V
DD
2
Single Supply Operation
Figure 6. Power Select Jumper Settings
OPERATING INSTRUCTIONS —
W EVAL BOARD
WTC32ND WITH WTC32ND-EV EVAL BOARD
Operate the WTC32ND quickly using the WTC32ND-EV
Evaluation Board. For integrating the WTC32ND into
a custom printed circuit board, see
.
NECESSARY EQUIPMENT
The following equipment is the minimum necessary to
configure the WTC and evaluation board for basic operation.
• WTC32ND Temperature Controller
• WTC32ND-EV PCB evaluation board
• Digital multimeter, 4-½ digit resolution recommended
• Thermistor or other temperature sensor
• Peltier-type thermoelectric module or resistive heater
• Optional: test load
• Minimum 22 gauge wiring
• Power Supplies (see below)
• Thermal Solutions Kit, if operating above 5 V or 500 mA
•
Small flathead screwdriver or Tweaker (included)
SYSTEM DESIGN DECISIONS
Before the WTC32ND-EV Evaluation Board can be
configured, several decisions must be made:
• What sensor is being used?
• What bias current is needed?
•
What is the operating maximum current and maximum
voltage?
• Will the power supply be a single or dual supply?
•
Will the system, as designed, fit within the Safe
Operating Area (SOA)?
POWER SUPPLY REQUIREMENTS
The V
DD
power supply is used to power the WTC32ND
internal control electronics and must be capable of sourcing
a minimum of 8 mA of current. If a fan is needed, the fan
draw current on V
DD
will also need to be added to the
minimum required current.
V
S
powers the WTC32ND output stage and must be sufficient
to provide 1.1 times quiescent current and TEC current.
V
S
= 1.1 * (I
TEC
+ V
S_QUIESCENT
)
For V
S
, when selecting a power supply, choose a voltage
as close to the operating voltage of the TEC as possible to
maximize efficiency and minimize the WTC internal power
dissipation.
SENSOR BIAS SWITCH
(100 µA shown)
VSET SOURCE JUMPER
(use onboard trimpot shown)
POWER SELECT JUMPER
(separate supplies shown)
SENSOR GAIN JUMPER
(GAIN = 1 shown)