Overview
The AD8495CRMZ is a precision instrumentation amplifier with a thermocouple cold junction compensator, designed and manufactured by Analog Devices Inc. This integrated circuit is specifically pretrimmed for K-type (chromel-alumel) thermocouples and provides a high-level output of 5 mV/°C directly from the thermocouple signal. It combines an ice point reference with a precalibrated amplifier, making it suitable for use as a standalone thermometer or as a switched output setpoint controller.
The device is known for its low cost, ease of use, and robust design, featuring internal cold junction compensation and high impedance differential inputs. It can operate with a wide range of supply voltages, from 2.7 V to 36 V, making it versatile for various applications, including industrial systems that require a wide common-mode input range.
Key Specifications
| Parameter | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Operating Voltage Range (Single Supply) | 2.7 | - | 36 | V |
| Operating Voltage Range (Dual Supply) | ±2.7 | - | ±18 | V |
| Quiescent Current | 180 | - | 250 | μA |
| Temperature Range (TA) - Specified Performance | 0 | - | 50 | °C |
| Temperature Range (TA) - Operational | -40 | - | 125 | °C |
| Input Voltage Range | -VS - 0.2 | - | +VS - 1.6 | V |
| Overvoltage Range | +VS - 25 | - | -VS + 25 | V |
| Input Bias Current | 25 | - | 50 | nA |
| Common-Mode Rejection | 1 | - | 0.3 | °C/V |
Key Features
- 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 withstand 4 kV ESD and provide over-voltage protection (OVP) up to VS ± 25 V.
- Differential inputs reject common-mode noise on the thermocouple leads.
- Reference pin voltage can be offset to measure 0°C on single supplies.
- Available in a small, 8-lead MSOP package that is fully RoHS compliant.
- High impedance differential input and low quiescent current to minimize self-heating.
Applications
- Industrial temperature measurement systems.
- Process control and automation.
- Aerospace and defense applications requiring precise temperature monitoring.
- Automotive systems for engine and exhaust temperature monitoring.
- Medical devices requiring accurate temperature measurements.
- General-purpose thermocouple-based temperature measurement systems.
Q & A
- What type of thermocouple is the AD8495CRMZ pretrimmed for?
The AD8495CRMZ is pretrimmed for K-type (chromel-alumel) thermocouples.
- What is the output voltage per degree Celsius for the AD8495CRMZ?
The output voltage is 5 mV/°C.
- What is the operating voltage range for the AD8495CRMZ?
The device can operate with a single supply from 2.7 V to 36 V or with dual supplies from ±2.7 V to ±18 V.
- How does the AD8495CRMZ handle common-mode noise?
The device features differential inputs that reject common-mode noise on the thermocouple leads.
- What is the quiescent current of the AD8495CRMZ?
The quiescent current is typically between 180 μA and 250 μA.
- Is the AD8495CRMZ RoHS compliant?
Yes, the AD8495CRMZ is available in a RoHS-compliant 8-lead MSOP package.
- What kind of protection does the AD8495CRMZ offer against ESD and overvoltage?
The device withstands 4 kV ESD and provides over-voltage protection (OVP) up to VS ± 25 V.
- Can the AD8495CRMZ be used as a standalone thermometer or setpoint controller?
Yes, the device can be used in both configurations due to its flexible pinout.
- How does the AD8495CRMZ minimize self-heating?
The device operates with a low quiescent current to minimize self-heating.
- What is the temperature range for specified performance of the AD8495CRMZ?
The specified performance temperature range is from 0°C to 50°C.
