Precision Thermocouple Amplifiers with Cold Junction Compensation AD8494/AD8495/AD8496/AD8497
FEATURES
Low cost and easy...
Precision Thermocouple
Amplifiers with Cold Junction Compensation AD8494/AD8495/AD8496/AD8497
FEATURES
Low cost and easy to use Pretrimmed for J or K type thermocouples Internal cold junction compensation High impedance differential input Standalone 5 mV/°C thermometer Reference pin allows offset adjustment Thermocouple break detection Laser wafer trimmed to 1°C initial accuracy and 0.025°C/°C ambient temperature rejection Low power: <1 mW at VS = 5 V Wide power supply range Single supply: 2.7 V to 36 V Dual supply: ±2.7 V to ±18 V Small, 8-lead MSOP
FUNCTIONAL BLOCK DIAGRAM
REF
+IN
ESD AND OVP
AD8494/AD8495/ AD8496/AD8497
A2
THERMOCOUPLE
COLD JUNCTION COMPENSATION
A3
OUT
–IN 1MΩ
ESD AND OVP
A1
SENSE
Figure 1.
APPLICATIONS
J or K type thermocouple temperature measurement Setpoint controller Celsius thermometer Universal cold junction compensator White goods (oven, stove top) temperature measurements Exhaust gas temperature sensing Catalytic converter temperature sensing
Table 1. Device Temperature Ranges
ThermoCouple Type J K J K Optimized Temperature Range Ambient Temperature Measurement (Reference Junction) Junction 0°C to 50°C Full J type range 0°C to 50°C Full K type range 25°C to 100°C Full J type range 25°C to 100°C Full K type range
Part No. AD8494 AD8495 AD8496 AD8497
GENERAL DESCRIPTION
The AD8494/AD8495/AD8496/AD8497 are precision instrumentation
amplifiers with thermocouple cold junction compensators on an integrated circuit. They produce a high le...