LTC2984 datasheet(13/22 Pages) LINER

13 / 22 page

dc2420f

DEMO MANUAL DC2420

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 LTC2984 RTD sensor modes. The DC2213 provides

severalcircuitsdemonstratingthefeaturesoftheLTC2984.

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

measured value of this sense resistor is stored in an on-

board EEPROM which the LTC2984 demo software can

read and use to configure the sense resistor value.

To demonstrate the low system noise of the LTC2984,

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

measurementerrorintroducedbyparasiticthermocouples.

To facilitate this measurement, the DC2213 provides an

external thermocouple interface which acts as a parasitic

thermocouple.

TO DC2399

DEMONSTRATION

BOARD

JUMPER

BYPASS/ENABLE

PARASITIC

THERMOCOUPLE

PARASITIC

THERMOCOUPLE

3-WIRE OR 4-WIRE

RTD

Figure 12. DC2213 Dedicated rTD Board

LTC2984 Datasheet(PDF) 13 Page - Linear Technology