METER THERMOMETERS

0˚C−100˚C Thermometer

DS005518-28

Calibration

2. Remove short, adjust R2 for correct reading in centigrade

Lower Power Thermometer

DS005518-29

†Select for operation at 1.3V

0˚F−50˚F Thermometer

DS005518-30

Calibration

2. Remove short, adjust R2 for correct reading in ˚F

Micropower Thermocouple Cold Junction

Compensator

DS005518-31

Adjustment Procedure

1. Adjust TC ADJ pot until voltage across R1 equals Kelvin temperature

multiplied by the thermocouple Seebeck coefficient.

2. Adjust zero ADJ pot until voltage across R2 equals the thermocouple

Seebeck coefficient multiplied by 273.2.

Thermocouple

Seebeck

R1

R2

Voltage

Voltage

Type

Coefficient

(

Ω)(Ω)

Across R1

Across R2

(µV/˚C)

@ 25˚C

(mV)

(mV)

J

52.3

523 1.24k

15.60

14.32

T

42.8

432

1k

12.77

11.78

K

40.8

412 953

Ω

12.17

11.17

S

6.4

63.4 150

Ω

1.908

1.766

Typical supply current 50 µA

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