LM135/LM235/LM335, LM135A/LM235A/LM335A
Fahrenheit Thermometer
569824
*To calibrate adjust R2 for 2.554V across LM336.
Adjust R1 for correct output.
THERMOCOUPLE COLD JUNCTION COMPENSATION
Compensation for Grounded Thermocouple
569806
*Select R3 for proper thermocouple type
THERMO-
COUPLE
J
T
K
S
R3
(±1%)
377Ω
308Ω
293Ω
45.8Ω
SEEBECK
COEFFICIENT
52.3 μV/°C
42.8 μV/°C
40.8 μV/°C
6.4 μV/°C
Adjustments:
Compensates for both sensor and resistor tolerances
1. Short LM329B
2. Adjust R1 for Seebeck Coefficient times ambient temperature (in degrees K) across R3.
3. Short LM335 and adjust R2 for voltage across R3 corresponding to thermocouple type.
J
14.32 mV
K
11.17 mV
T
11.79 mV
S
1.768 mV
9
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