Overview
The AD8497CRMZ-R7, produced by Analog Devices Inc., is a precision instrumentation amplifier with thermocouple cold junction compensation integrated into a single IC package. This device is specifically calibrated to match the characteristics of K-type (chromel-alumel) thermocouples. It provides a high-level output of 5 mV/°C directly from the thermocouple signal, combining an ice point reference with a precalibrated amplifier. The AD8497 can be used as a standalone thermometer or as a switched output setpoint controller, offering flexibility in various temperature measurement applications.
Key Specifications
| Parameter | Value |
|---|---|
| Input Voltage Range | −VS − 0.2 to +VS − 1.6 V |
| Overvoltage Range | −VS + 25 to +VS − 25 V |
| Input Bias Current | 25 nA |
| Input Offset Current | 1.5 nA |
| Common-Mode Rejection | 1 °C/V (VCM = 0 V to 3 V) |
| Power Supply Rejection | 0.5 °C/V (+VS = 2.7 V to 5 V) |
| Voltage Noise (0.1 Hz to 10 Hz, TA = 25°C) | 0.8 μV p-p |
| Voltage Noise Density (f = 1 kHz, TA = 25°C) | 32 nV/√Hz |
| Current Noise Density (f = 1 kHz, TA = 25°C) | 100 fA/√Hz |
| Output Voltage Range | −VS + 0.025 to +VS − 0.1 V |
| Short-Circuit Current | 7 mA |
| −3 dB Bandwidth | 25 kHz (AD8495/AD8497) |
| Settling Time to 0.1% (4 V output step) | 40 μs (AD8495/AD8497) |
| Supply Voltage Range | 2.7 V to 36 V |
| Package Type | 8-Lead MSOP |
Key Features
- Precision Thermocouple Signal Conditioning: The AD8497 provides a complete, precision laser wafer trimmed thermocouple signal conditioning system in a single IC package.
- Flexible Pinout: Allows operation as a setpoint controller or as a standalone Celsius thermometer.
- Rugged Inputs: Inputs withstand 4 kV ESD and provide overvoltage protection (OVP) up to VS ± 25 V.
- Differential Inputs: Reject common-mode noise on the thermocouple leads.
- Reference Pin Voltage Offset: Can be offset to measure 0°C on single supplies.
- Low Power Consumption: Typically operates with a total supply current of 180 μA.
- Wide Supply Voltage Range: Can operate with supplies from 2.7 V to 36 V.
- Compact Package: Available in a small, 8-lead MSOP package that is fully RoHS compliant.
Applications
- Industrial Temperature Measurement: Suitable for industrial systems requiring a wide common-mode input range.
- Automotive Systems: Can be used in automotive applications where robust and precise temperature measurement is necessary.
- Medical Devices: Applicable in medical devices that require accurate and reliable temperature monitoring.
- Aerospace and Defense: Used in aerospace and defense applications where high precision and reliability are critical.
- Process Control: Ideal for process control systems that need precise temperature measurements and control.
Q & A
- What type of thermocouple does the AD8497CRMZ-R7 support?
The AD8497CRMZ-R7 is calibrated to match the characteristics of K-type (chromel-alumel) thermocouples.
- What is the output voltage range of the AD8497CRMZ-R7?
The output voltage range is −VS + 0.025 to +VS − 0.1 V.
- What is the typical supply current of the AD8497CRMZ-R7?
The device typically operates with a total supply current of 180 μA.
- Can the AD8497CRMZ-R7 be used as a setpoint controller?
Yes, it can be used as a setpoint controller or as a standalone Celsius thermometer.
- What is the common-mode rejection ratio (CMRR) of the AD8497CRMZ-R7?
The CMRR is 1 °C/V for VCM = 0 V to 3 V.
- What is the bandwidth of the AD8497CRMZ-R7?
The −3 dB bandwidth is 25 kHz for the AD8495/AD8497 models.
- Is the AD8497CRMZ-R7 RoHS compliant?
Yes, it is fully RoHS compliant.
- What is the maximum ESD protection for the inputs of the AD8497CRMZ-R7?
The inputs withstand 4 kV ESD.
- Can the AD8497CRMZ-R7 operate with low supply voltages?
Yes, it can operate with supplies as low as 2.7 V.
- What is the settling time of the AD8497CRMZ-R7 to 0.1% for a 4 V output step?
The settling time is 40 μs for the AD8495/AD8497 models.
