Newport LDC-3706 Series, User Manual

Page: 45 / 124

December 2019 33 LDC-3706 Series Laser Controller
IC-I SENSORS – When an IC-I sensor is selected, the LDC-3706 Laser Controller measures
temperature based on the current passed through the sensor. An example of an IC-I sensor is
the Analog Devices AD590. This device delivers 1 µA/K or approximately 298 µA at 25°C. The
(+) terminal of the transducer should be connected to the pin and the (-) terminal
should be connected to Sensor-. The nominal slope for the AD590 is 1 µA/K and the offset is
nominally 0 µA but both can be adjusted to calibrate a particular sensor by entering the TEC
parameter menu.
The sensor will have approximately 9 V across it at 25°C but will vary over the temperature
range. In IC-I sensor mode, the LDC-3706 has a sensor current limit of 600 µA, which is
approximately 325°C.
For IC-Current sensors used with the LDC-3706 the 4-wire sensor measurements
(pins 7 and 8) should not be connected. The use of the 4-wire sensor will cause
inaccurate sensor measurements.
IC-V SENSORS – When an IC-V sensor is selected the LDC-3706 instrument measures
temperature based on the voltage across the sensor. An example of an IC-V sensor is the
National Semiconductor LM335A. This device delivers 10 mV/K or approximately 2.98 V at
25°C. The (+) terminal of the transducer should be connected to the pin and the (-)
terminal should be connected to Sensor-. The nominal slope for the LM335A is 10 mV/K and
the offset is nominally 0 mV but both can be adjusted to calibrate a particular sensor by entering
the PARAM menu.
The sensor will have approximately 1 mA of current through it at all times. In IC-V sensor mode,
the LDC-3706 instrument has a sensor voltage limit of 6 V, which is approximately 325°C.