AD8495 Full K-Type Range 0° to 50° Thermocouple Amplifier w/Cold Junction Compensation

Complete, precision laser wafer trimmed thermocouple signal conditioning system in a single IC package. Flexible pinout provides for 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 that is fully RoHS compliant. Applications div#landing_page_sec ul { padding:0 0 15px 10px; margin:0px; } div#landing_page_sec li { padding:3px 0 2px 20px; margin:0px; list-style:none; background:url(/static/imported-files/embedded_html/images/li_img.gif) no-repeat 7px 9px; display:block; color:#000000; font-family: Arial, Helvetica, sans-serif; }

The AD8494/AD8495/AD8496/AD8497 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 AD8494/AD8495/AD8496/AD8497 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 AD8494 and AD8496 are precalibrated by laser wafer trimming to match the characteristics of J type (iron-constantan) thermocouples; the AD8495 and AD8497 are laser trimmed to match the characteristics of K type (chromel-alumel) thermo-couples. See Table 1 on the data sheet for the optimized ambient temperature range of each part.

The AD8494/AD8495/AD8496/AD8497 allow a wide variety of supply voltages. With a 5 V single supply, the 5 mV/°C output allows the devices to cover nearly 1000 degrees of a thermo-couple’s temperature range.

The AD8494/AD8495/AD8496/AD8497 work with 3 V supplies, allowing them to interface directly to lower supply ADCs. They can also work with supplies as large as 36 V in industrial systems that require a wide common-mode input range.

Product Highlights

Applications

Features and Benefits
  • Low cost and easy to use
  • Pretrimmed for K type thermocouples
  • Internal cold junction compensation
  • High impedance differential input
  • Standalone 5 mV/°C thermometer
  • Reference pin allows offset adjustment
  • Thermocouple break detection
  • See data sheet for additional features.
  • Amplifiers
    Sensors
    Building Technology
    • White Goods and Vending
    SPICE Models
    Reference Designs
    Data Sheets
    Documentnote
    AD8494/AD8495/AD8496/AD8497: Precision Thermocouple Amplifiers with Cold Junction Compensation Data Sheet (Rev. C)PDF 2214 kB
    Application Notes
    Documentnote
    AN-1087: Thermocouple Linearization When Using the AD8495/AD8496/AD8497 (Rev. 0)PDF 126 kB
    Order Information
    Part NumberPackagePacking QtyTemp RangePrice 100-499Price 1000+RoHS
    AD8495ARMZ Production8 ld MSOPOTH 50-40 to 125C2.191.75Y
    AD8495ARMZ-R7 Production8 ld MSOPREEL 1000-40 to 125C2.191.75Y
    AD8495CRMZ Production8 ld MSOPOTH 50-40 to 125C3.883.1Y
    AD8495CRMZ-R7 Production8 ld MSOPREEL 1000-40 to 125C3.883.1Y
    Reference Materials
    AD8494/AD8495/AD8496/AD8497:集成冷结温度补偿的精密热电偶放大器 数据手册 (Rev. A) ad8495
    AD8494/AD8495/AD8496/AD8497: Precision Thermocouple Amplifiers with Cold Junction Compensation Data Sheet (Rev. C) ad8495
    AD8495 SPICE Macro-Model ad8495
    CN0354 Design & Integration Files adg1609
    CN0271 设计和集成文件 ad8495
    AN-1087: 使用AD8494/AD8495/AD8496/AD8497时的热电偶线性化 (Rev. 0) ad8495
    AN-1087: Thermocouple Linearization When Using the AD8495/AD8496/AD8497 (Rev. 0) ad8495
    Two Ways to Measure Temperature Using Thermocouples Feature Simplicity,... ad8495
    CN-0271:集成冷结补偿的K型热电偶测量系统 ad8495