AD8497 AD [Analog Devices], AD8497 Datasheet - Page 4

• Manufacturer Part Number: AD8497
• Description: Precision Thermocouple Amplifiers with Cold Junction Compensation
• Manufacturer: AD [Analog Devices]

AD8494/AD8495/AD8496/AD8497
Parameter
TEMPERATURE RANGE (T
1
2
3
4
5
6
Ambient temperature rejection specifies the change in the output measurement (in °C) for a given change in temperature of the cold junction. For the AD8494 and
AD8495, ambient temperature rejection is defined as the slope of the line connecting errors calculated at 0°C and 50°C ambient temperature. For the AD8496 and
AD8497, ambient temperature rejection is defined as the slope of the line connecting errors calculated at 25°C and 100°C ambient temperature.
Error does not include thermocouple gain error or thermocouple nonlinearity.
With a 100 kΩ load, measurement junction temperatures beyond approximately 880°C for the AD8494 and AD8496 and beyond approximately 960°C for the AD8495
and AD8497 require supply voltages larger than 5 V or a negative voltage applied to the reference pin. Measurement junction temperatures below 5°C require either a
positive offset voltage applied to the reference pin or a negative supply.
Input stage uses PNP transistors, so bias current always flows out of the part.
Large output currents can increase the internal temperature rise of the part and contribute to cold junction compensation (CJC) error.
Unbalanced supplies can also be used. Care should be taken that the common-mode voltage of the thermocouple stays within the input voltage range of the part.
Specified Performance
Operational
AD8494/AD8495
AD8496/AD8497
A
)
Test Conditions/Comments
Rev. 0 | Page 4 of 16
Min
−40
0
25
A Grade
Typ
Max
50
100
+125
Min
0
25
−40
C Grade
Typ
Max
50
100
+125
Unit
°C
°C
°C