AD8494CRMZ Analog Devices Inc, AD8494CRMZ Datasheet
AD8494CRMZ
Specifications of AD8494CRMZ
Related parts for AD8494CRMZ
AD8494CRMZ Summary of contents
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... 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 ± ...
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... Changes to Figure 1 .......................................................................... 1 Changes to Figure 33 and Figure 34 ............................................. 14 Changes to Figure 35 and Figure 36 ............................................. 15 Changes to Ordering Guide .......................................................... 16 10/10—Rev Rev. A Changes to Linearity Error of the Thermocouple Section ........ 12 Changes to Ambient Temperature Sensor Section .................... 14 Changes to Ordering Guide .......................................................... 16 7/10—Revision 0: Initial Version Thermocouples ........................................................................... 11 Thermocouple Signal Conditioner .......................................... 11 AD8494/AD8495/AD8496/AD8497 Architecture .................. 11 Maximum Error Calculation ...
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... POWER SUPPLY Operating Voltage Range 6 Single Supply Dual Supply Quiescent Current = 25° 100 kΩ, unless otherwise noted. Specifications do not include REF the ambient temperature at the AD849x Grade Min Typ = T = 25° 60° 175° 0°C to 50°C = 25°C to 100°C 5 −V – ...
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... With a 100 kΩ load, measurement junction temperatures beyond approximately 880°C for the AD8494 and AD8496 and beyond approximately 960°C for the AD8495 and AD8497 require supply voltages larger than negative voltage applied to the reference pin. Measurement junction temperatures below 5°C require either a positive offset voltage applied to the reference pin or a negative supply ...
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... Minimum Voltage at −IN or +IN REF Voltage Output Short-Circuit Current Duration Storage Temperature Range Operating Temperature Range Maximum IC Junction Temperature ESD Human Body Model Field-Induced Charged Device Model Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only ...
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AD8494/AD8495/AD8496/AD8497 PIN CONFIGURATION AND FUNCTION DESCRIPTIONS Table 5. Pin Function Descriptions Pin No. Mnemonic Description 1 −IN Negative Input. 2 REF Reference. This pin must be driven by low impedance. 3 −V Negative Supply Connect. 5 ...
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... Figure 5. Frequency Response 1k 10k 100k 10k 100k Figure 7. Input Common-Mode Voltage Range vs. Output Voltage 100k 1M Figure 8. Input Bias Current and Input Offset Current vs. Temperature Rev Page AD8494/AD8495/AD8496/AD8497 1200 1000 CONNECTED THERMOCOUPLE 800 600 400 200 OPEN THERMOCOUPLE 0 THERMOCOUPLE CONNECTION AD849x OUTPUT –200 TIME (50µ ...
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AD8494/AD8495/AD8496/AD8497 3.00 2.75 2.50 V OUT 2.25 2.00 1.75 1.50 1.25 I 1.00 IN 0.75 0.50 0.25 0 –30 –25 –20 –15 –10 – INPUT VOLTAGE (V) Figure 9. AD8494 Input Overvoltage Performance, +V 3.00 2.75 2.50 ...
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Figure 15. AD8494/AD8496 Small-Signal Response with Various Capacitive Loads 120µs/DIV Figure 16. Small-Signal Response 100 kΩ 2V/DIV SETTLING TO 0.1% IN 40µs 0.02%/DIV 100µs/DIV Figure 17. AD8495/AD8497 Large-Signal Step Response and Settling Time C = ...
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AD8494/AD8495/AD8496/AD8497 1s/DIV Figure 21. 0 RTI Voltage Noise –1 –2 –3 –4 –5 1k 10k LOAD RESISTANCE (Ω) Figure 22. Output Voltage Swing vs. Load Resistance, V 100 90 80 ...
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... A thermocouple is a rugged, low cost temperature transducer whose output is proportional to the temperature difference between a measurement junction and a reference junction. It has a very wide temperature range. Its low level output (typically tens of microvolts per °C) requires amplification. Variation in the reference junction temperature results in measurement error unless the thermocouple signal is properly compensated ...
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... AD8495 K ±2°C AD8496 J ±2°C AD8497 K ±2°C For temperature ranges outside those listed in Table 7 or for instructions on how to correct for thermocouple nonlinearity error with software, see the additional details. Rev Page Ambient Measurement Temperature Temperature Range Range 0° ...
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... Debugging Tip If the AD849x is not providing the expected performance, a useful debugging step is to implement the ambient temperature configuration in Figure 34. If the ambient temperature sensor does not work as expected, the problem is likely with the AD849x or with the downstream circuitry. If the ambient temperature sensor configuration is working correctly, the problem typically lies with how the thermocouple is connected to the AD849x ...
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... COUPLE –IN 1 AD849x 1MΩ 2 –V REF Figure 33. Basic Connection for the AD849x To measure negative temperatures, apply a voltage at the refer- ence pin to offset the output voltage at 0°C. The output voltage of the AD849x × 5 mV/° OUT MJ REF A filter at the input is recommended to remove high frequency noise. The 1 MΩ ...
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... S 7 REFERENCE PIN ALLOWS OFFSET ADJUSTMENT The reference pin can be used to level-shift the AD849x output voltage. This is useful for measuring negative temperatures on a SENSE 5 single supply and to match the AD849x output voltage range to 6 the input voltage range of the subsequent electronics in the ...
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... Model 1 Temperature Range AD8494ARMZ −40°C to +125°C AD8494ARMZ-R7 −40°C to +125°C AD8494CRMZ −40°C to +125°C AD8494CRMZ-R7 −40°C to +125°C AD8495ARMZ −40°C to +125°C AD8495ARMZ-R7 −40°C to +125°C AD8495CRMZ −40°C to +125°C AD8495CRMZ-R7 −40°C to +125°C AD8496ARMZ − ...