AD8495ARMZ Analog Devices Inc, AD8495ARMZ Datasheet
AD8495ARMZ
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AD8495ARMZ Summary of contents
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FEATURES Low cost and easy to use Pretrimmed for 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 ...
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AD8494/AD8495/AD8496/AD8497 TABLE OF CONTENTS Features .............................................................................................. 1 Applications ....................................................................................... 1 Functional Block Diagram .............................................................. 1 General Description ......................................................................... 1 Product Highlights ........................................................................... 1 Revision History ............................................................................... 2 Specifications ..................................................................................... 3 Absolute Maximum Ratings ............................................................ 5 Thermal Resistance ...................................................................... 5 ESD ...
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SPECIFICATIONS + − +IN −IN gain and offset errors of the thermocouple itself. T temperature the thermocouple measurement junction temperature. MJ Table 2. ...
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AD8494/AD8495/AD8496/AD8497 Parameter Test Conditions/Comments TEMPERATURE RANGE ( Specified Performance AD8494/AD8495 AD8496/AD8497 Operational 1 Ambient temperature rejection specifies the change in the output measurement (in °C) for a given change in temperature of the cold junction. For the AD8494 ...
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ABSOLUTE MAXIMUM RATINGS Table 3. Parameter Supply Voltage Maximum Voltage at −IN or +IN 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 ...
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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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TYPICAL PERFORMANCE CHARACTERISTICS T = 25° ∞, unless otherwise noted 100 AD8495/AD8497 AD8494 AD8496 10 1 0.1 0.01 0 100 FREQUENCY (Hz) Figure 3. CMRR vs. Frequency 1000 AD8495/AD8497 ...
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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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THEORY OF OPERATION THERMOCOUPLES 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 ...
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AD8494/AD8495/AD8496/AD8497 The small thermocouple voltages mean that signals are quite vulnerable to interference, especially when measured with single-ended amplifiers. The AD849x addresses this issue in several ways. Low input bias currents and high input impedance allow for easy filtering at ...
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RECOMMENDATIONS FOR BEST CIRCUIT PERFORMANCE Input Filter A low-pass filter before the input of the AD849x is strongly recommended (see Figure 29), especially when operating in an electrically noisy environment. Long thermocouple leads can function as an excellent antenna and ...
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AD8494/AD8495/AD8496/AD8497 APPLICATIONS INFORMATION BASIC CONNECTION Figure 33 shows an example of a basic connection for the AD849x, with a J type or K type thermocouple input. COLD JUNCTION COMPENSATION +IN 8 THERMO- IN-AMP COUPLE –IN 1 AD849x 1MΩ 2 –V ...
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SETPOINT CONTROLLER The AD849x can be used as a temperature setpoint controller, with a thermocouple input from a remote location or with the AD849x itself being used as a temperature sensor. When the measured temperature is below the setpoint temperature, ...
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... 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 −40°C to +125°C AD8496ARMZ-R7 − ...