Linear Technology ANALOG DEVICES DC2608 Manual page 13

HARDWARE SETUP
DC2213 DEDICATED RTD BOARD
The DC2213 dedicated RTD board (see Figure 12) dem-
onstrates the flexibility, accuracy, and low noise features
of the LTC2986-1 RTD sensor modes. The DC2213 pro-
vides several circuits demonstrating the features of the
LTC2986-1.
The DC2213 (see schematic diagram Figure 13 and cor-
responding software configuration Figure 14) provides a
2kΩ ±0.1% 10ppm/°C sense resistor on channels 2 and
3 which may be used with any of the RTD sensor circuits
on this board. An additional Kelvin connection is also
provided to this sense resistor on channel 1. The precise
DEMO MANUAL DC2608
measured value of this sense resistor is stored in an on-
board EEPROM which the LTC2986-1 demo software can
read and use to configure the sense resistor value.
To demonstrate the low system noise of the LTC2986-1,
the dedicated RTD board provides a 0°C PT100 simulator
(100Ω ±0.01% 10ppm/°C) on channels 3 to 6 configured
as a 4-wire sensor. In addition to this the user may use this
circuit to demonstrate how the rotated mode eliminates
measurement error introduced by parasitic thermocouples.
To facilitate this measurement, the DC2213 provides an
external thermocouple interface which acts as a parasitic
thermocouple.
Figure 12. DC2213 Dedicated RTD Board
dc2608f
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