ETC HY-5610

hytek
HY-5610
TEC CONTROLLER
Microsystems
11/97
SUBMINIATURE CONTROLLER FOR THERMOELECTRIC COOLERS
FEATURES:
> PROPORTIONAL CONTROL
> SMALL SIZE
> DRIVE CURRENT TO +/- 2 AMPS
> OPERATION TO 12 VOLTS
> CONTROL ABOVE/BELOW AMBIENT
ACTUAL SIZE
DESCRIPTION:
MAXIMUM RATINGS:
The HY-5610 is a subminiature proportional
temperature controller for thermoelectric
coolers (TEC). This device is intended for
“heat or cool” fixed temperature applications
where front panel controls and digital readouts
are not required. The HY-5610 uses a
thermistor bridge to precisely measure and
regulate the temperature of a device affixed
to a TEC. With proper heat sinking the power
stage of this device will deliver up to +/- 2
Amperes of current to a TEC and will
operate from a 5 to 12 Volt power supply.
FIGURE 1
RCH
Rating
Symbol
Value
Unit
Supply Voltage 1 (Voltage on Pin 8)
VDD
+20
Volts DC
Supply Voltage 2 (Voltage on Pin 10)
VS
+12
Volts DC
Current Sink (Heat and Cool Cycle)
IS
2.5
Amperes
Maximum Power Dissipation
PMAX
6
Watts
Operating Temperature (Case)
TMAX
120
°C
Storage Temperature
TSTG
-65 to +150
°C
SIMPLIFIED SCHEMATIC OF THE HY-5610
SHOWN WITHIN THE DASHED LINES
THERMISTOR
RCC
SIGNAL
COMMON
RS
RG
THIS IS THE CURRENT LIMIT RESISTOR
FOR THE HEAT CYCLE.
RCC
THIS IS THE CURRENT LIMIT RESISTOR
FOR THE COOLING CYCLE.
RT
-
RL CL
RCH
VS
+
THERMOELECTRIC
COOLER
7
6
5
3
9
13
1
V/I
20
+
PWR.
GND
PIN
N0.
1
VDD
+
2
10
11
12
8
+5V
1
V/I
20
+2.5V
10 MΩ
+1.25V
V/I
+1.25V
THERMISTOR
BRIDGE AMPLIFIER
V/I
V
+2.5V
INTEGRATOR
The Signal Common and the Power
Ground are connected internally to
the HY-5610 to avoid ground loops.
hytek Microsystems
VOLTAGE TO CURRENT
CONVERTER
POWER STAGES
10KΩ
10KΩ
VOLTAGE
INVERTER
+2.5V
400 Hot Springs Rd. Carson City NV 89706 (702) 883-0820 Fax -0827 www.hytek.com
hytek
HY-5610
TEC CONTROLLER
Microsystems
DESCRIPTION OF THE HY-5610 PIN OUTS
*
Temperature Set Resistor Rs (Pin 1 to Pin 7)
The temperature set resistor for the HY-5610 controls the temperature at which the TEC will operate. When the circuit
has stabilized, the resistance of the thermistor will be equal to that of the set resistor Rs. For example, if a Dale 10kΩ
thermistor is used as the temperature sensing device, a set resistor of approximately 56kΩ will set an operating
temperature of -10oC. A graph of Rs vs. set temperature is shown in figure 4 when using a Dale 1M1002 thermistor.
*
Thermistor, R T (Pin 6 to Pin 7)
The thermistor should be located in close proximity to the device being temperature controlled by the TEC. It should
be in good thermal contact to avoid stability problems.
The HY-5610 has been designed for a negative temperature coefficient thermistor. A thermistor with a positive
temperature coefficient can also be used if the position of the temperature set resistor and temperature sensing resistor
are changed. The same result can also be achieved by reversing the leads of the TEC in which case Rcc & RCH must
be interchanged.
* Gain Set Resistor, RG (Pin 5 to Pin 6)
The ratio of the gain set resistor RG to R L controls the response time of the servo loop. A ratio that is too large can
cause slow response and a ratio that is too small can cause loop instability. In most applications RG may not be
needed since a 10MΩ resistor is internal to the HY-5610 and generally provides enough gain for good operation.
* Loop Stability Network, RL and CL (Pin 3 to Pin 5)
The RC time constant of these two components is a first approximation of the thermal time constant of the servo loop.
The thermal time constant of the combination of the device being cooled, the thermistor, and the TEC can be
approximated by applying constant power to the TEC and measuring the length of time it takes to reach 66% of it’s
final temperature.
For example, if the thermal time constant was observed to be 5 seconds, then a 1uF capacitor and a 4.7MΩ could be
chosen as the loop stabilizing components. Typical values for loop compensation components are shown in Table 1.
Note: The values of RG, RL, and CL are generally selected by experiment. CL should be a low leakage nonpolarized
capacitor.
* Current Limit Resistors, Rcc & RCH (Pin 1 to Pin 3, and Pin 1 to Pin 2)
These resistors limit the maximum current that the HY-5610 can supply to the TEC when in the cooling cycle and in
the heating cycle. Rcc limits the maximum current for the cooling cycle and RCH limits the maximum current in the
heating cycle. This feature prevents damage to the TEC during turn-on. It is also often desirable to limit the
maximum value of heating current as much as 30% less than the maximum cooling current. This is because TECs
are much more efficient heating than cooling. Figure 5 shows the approximate values for Rcc & RCH required to
program a desired turn-on current. For example an Rcc value of 18KΩ will limit the maximum cooling current to 2
Amperes and an RCH value of 13.5KΩ will limit the maximum heating current to 0.6 Amperes.
* VDD (Pin 8 to Pins 11 & 12) +7 < VDD < +20 Volts
This input supplies the voltage to the internal circuitry of the HY-5610. The maximum current drain at this terminal is 5mA.
* Vs (Pin 10 to Pins 11 & 12) +3 < Vs < +12 Volts
This input supplies the voltage to the HY-5610 power drive circuitry. The maximum current drain at this terminal
should not exceed 2 Amperes.
* Thermoelectric Cooler, TEC (Pin 9 to Pin 13)
The cooling lead of the TEC should be connected to Pin 9 and the heating lead should be connected to Pin 13 of the
HY-5610. If the temperature of the thermistor is greater than the set temperature at turn-on, maximum cooling current
will flow into Pin 9 and out of Pin 13. Conversely, maximum heating current will flow into Pin 13 and out of Pin 9 if the
temperature of the thermistor is less than the set temperature at turn-on. The maximum turn-on current is limited by Rcc
and RCH. Once the TEC reaches it’s set temperature, the current through the TEC will decrease to exactly the value
required to maintain the correct set temperature.
hytek Microsystems
400 Hot Springs Rd. Carson City NV 89706 (702) 883-0820 Fax -0827 www.hytek.com
hytek
HY-5610
TEC CONTROLLER
Microsystems
HY-5610 CURRENT SOURCE
CHARACTERISTICS
11/97
CONSTANT
POWER
CURVE = 6 WATTS
ON RESISTANCE
OF CURRENT
SINK
Figure 2 illustrates the characteristics of
the HY-5610 power drive section. It also
illustrates the unsafe operating area
where the power dissipated in the device
exceeds the maximum 6 watt rating.
This curve applies for both heating and
cooling operation.
2.0
UNSAFE
OPERATING
AREA
Note that the resistance of the power
drive section is approximately one ohm
when the HY-5610 is fully turned on.
1.0
0
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
VOLTS
FIGURE 2
SUPPLY VOLTAGE ( VS )
PIN 10 TO GROUND (PIN 11 & 12)
Figure 3 illustrates the locus of operating
current and voltage for two different TECs.
Example 1:
A supply voltage of 5 Volts was chosen for
use with the ITI Ferro Tek Model
6300/018/018A TEC. This device is rated for
a maximum current of 1.8 Amperes at a
maximum allowable voltage of 2.7 Volts.
This is a load resistance of approximately
1.5 ohms. The intersection of the 1.5 ohm
load line and the HY-5610 current source
characteristic's define the locus of operation
voltage and current for both the HY-5610
and the TEC. In this application the current
was limited to 1.8 Amperes when cooling and
to 0.6 Amperes when heating by proper
selection of RCC & RCH.
DETERMINATION OF THE
HY-5610 OPERATING
POINTS USING LOAD LINES
LOAD LINE FOR A
ITI Ferro Tec MODEL
6300/018/018A TEC (1.5Ω)
2.0
UNSAFE
OPERATING
AREA
Example 2:
1.0
LOAD LINE FOR
A MELCOR MODEL
FC 0.45-66-05 TEC
0
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
A supply voltage of 12 Volts was chosen for
the Melcor FC 0.45-66-05 TEC. This device
has a maximum rated voltage of 7.98 Volts
at a current of 0.8 Amperes. A load line for
this device is also shown on the plot. Once
again maximum turn on current is set by
proper selection of RCC & RCH.
VOLTS
FIGURE 3
SUPPLY VOLTAGE ( VS )
PIN 10 TO GROUND (PIN 11 & 12)
hytek Microsystems
Note that the power dissipated in the HY5610 never exceeds the 6 Watt maximum
power dissipation in both of these examples.
400 Hot Springs Rd. Carson City NV 89706 (702) 883-0820 Fax -0827 www.hytek.com
hytek
HY-5610
TEC CONTROLLER
Microsystems
11/97
TEMPERATURE SET
RESISTOR Rs
vs
SET TEMPERATURE
APPROXIMATE VALUE OF CURRENT
LIMIT SET RESISTOR Rc
vs
MAXIMUM SINK CURRENT
100
20
19
90
DALE 10KΩ
THERMISTOR
TYPE 1M1002
80
70
18
17
60
16
50
15
40
14
30
13
20
12
15
11
10
10
-25 -20 -15
FIGURE 4
-10 -5
0
5
10
15
20
25
0
TEMPERATURE °C
0.2
0.4 0.6
FIGURE 5
0.8 1.0 1.2
1.4 1.6
1.8 2.0 2.2
MAXIMUM SINK CURRENT (Is)
AMPERES
MECHANICAL DIMENSIONS
PIN 1
IDENTIFIER
TYPICAL RESISTOR
AND CAPACITOR VALUES
FOR VARIOUS THERMAL
TIME CONSTANTS
SLOT FOR 2-56
SCREWS
2 PLACES
ALUMINUM
BASE
LEADS ON
0.100"
CENTERS
THERMAL TIME
CONSTANT
T (SECONDS)
1
13
2
3
4
HYTEK
12
HY-5610
5
6
1
2
3
5
10
15
20
14
11
0.720"
10 MΩ
20 MΩ
3 MΩ
4.7 MΩ
10 MΩ
15 MΩ
20 MΩ
0.1 µF
0.1 µF
1.0 µF
1.0 µF
1.0 µF
1.0 µF
1.0 µF
100KΩ
to
10MΩ
NOTES:
8
1. Make sure the heat sink to
which the HY-5610 is mounted is
flat and clean, otherwise the
ceramic substrate may break.
0.110"
0.090"
DATE
CODE
0.300"
Rg
TABLE 1
9
7
CL
0.950" 1.150"
10
9326
RL
0.040"
0.600"
0.060"
0.900"
0.220"
MAX.
0.720"
0.300"
MIN
2. Use a thermal compound
such as Dow Corning 340
between the HY-5610 and the
heat sink for good thermal
conduction.
3. Note that the Pin 1 identifier
is shown in a bottom view. From
a top view, Pin numbers ascend
in clockwise fashion.
Specifications Subject to Change
Without Notice.
hytek Microsystems
400 Hot Springs Rd. Carson City NV 89706 (702) 883-0820 Fax -0827 www.hytek.com