Instrumentation Amplifier, Thermocouple Type K, 25 kHz, MSOP-8

AD 8495 A
The AD8495 are precision instrumentation amplifiers with thermocouple cold junction compensators on an integrated circuit. They produce a high level (5 mV/°C) output directly from a thermocouple signal by combining an ice point reference with a precalibrated amplifier. They can be used as standalone thermometers or as switched output setpoint controllers using either a fixed or remote setpoint control.
The AD8495 can be powered from a single-ended supply (less than 3 V) and can measure temperatures below 0°C by offsetting the reference input. To minimize self-heating, an unloaded AD849x typically operates with a total supply current of 180 µA, but it is also capable of delivering in excess of ±5 mA to a load.
The AD8495 are precalibrated by laser wafer trimming to match the characteristics of J type (iron-constantan) thermocouples. See Table 1 for the optimized ambient temperature range.

- 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

APPLICATIONS
- 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