Improving Regulation of Adjustable Regulators

20156207

Micropower Thermocouple Cold Junction Compensator

20156206

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.

Seebeck

Voltage

Voltage

Thermocouple

Co-

R1

R2

Across R1

Across R2

Type

efficient

(

Ω)(Ω)

(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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