AD8495 Amplifiers Introduction
 Figure 1 AD8495ARMZ |
 Figure 2 Pin Configuration |
 Figure 3 Functional Block Diagram |
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WHAT IS AD8495ARMZ ?
The AD8495ARMZ is an instrumentation amplifier with thermocouple cold junction compensator on an integrated circuit. The effects of temperature change on dissimilar metals (Thermocouple) produces a measurable voltage. But to make that measurement you need an amplifier circuit (A8495ARMZ) designed for the thermocouple being used. This device incorporates precision instrumentation amplifiers provide an amplified output directly from a type J or K thermocouples. The AD8495ARMZ can be powered from a single-ended supply and can measures temperature below 0°C. They can be used as a thermometers or as switched output setpoint controllers.
PINOUT DISCRIPTION
Table 1 PIN Configuration
| PIN NO. | LABLE | DESCRIPTION | |
| 1 | -IN | Connect this pin with -Ve terminal of thermocouple | |
| 2 | REF | Reference | |
| 3 | VS | -Ve Supply | |
| 4 | NC | No Connect (Floating) | |
| 5 | SENSE | Sense Pin | |
| Measurement Mode | Connect to Output | ||
| Setpoint Mode | Connect to Setpoint Voltage | ||
| 6 | OUT | Output | |
| 7 | +VS | Positive Supply | |
| 8 | +IN | Connect this pin with +Ve terminal of thermocouple | |
ABSOLUTE MAXIMUM RATINGS*
| PARAMETER | VALUE |
| Supply Voltage | ±18 V |
| Maximum Voltage at −IN or +IN | −VS + 25 V |
| Minimum Voltage at −IN or +IN | +VS − 25 V |
| REF Voltage | ±VS |
| Operating Temperature Range | −40°C to +125°C |
| Maximum IC Junction Temperature | 140°C |
*Operation beyond the maximum operating conditions for extended periods may affect product reliability.
FEATURES
- Low cost
- Easy to operate
- suitable for J or K type thermocouples
- Internal cold junction compensation (for monitoring changes in cold junction)
- High impedance differential input
- Can be used as Thermometer
- offset adjustment
- Thermocouple break detection
- Laser wafer trimmed to 1°C initial accuracy
- ambient temperature rejection
- Low power consumption
- Wide power supply range
- Single supply: 2.7 V to 36 V
- Dual supply: ±2.7 V to ±18 V
ALTERNATIVES FOR AD8495ARMZ
Table 2 equivalent for AD8495
| IC NUMBER | THERMOCOUPLE
TYPE |
TEMPRATURE RANGE | |
| REFERENCE JUNCTION | MEASUREMENT JUNCTION | ||
| AD8495 | K | 0°C to 50°C | Full K type range |
| AD8494 | J | 0°C to 50°C | Full J type range |
| AD8496 | J | 25°C to 100°C | Full J type range |
| AD8497 | K | 25°C to 100°C | Full K type range |
APPLICATION | FUNCTION
- J or K type thermocouple temperature measurement
- Setpoint controller
- Celsius thermometer
- Universal cold junction compensator
- White goods (oven, stove top) temperature measurements
- Exhaust gas temperature sensing
- Catalytic converter temperature sensing
HOW TO USE AD8495ARMZ ? | Working of AD8495ARMZ
Fig.4 Shows connection of AD8495 with K type thermocouple. A filter at the input is recommended to remove high frequency noise. The 1 MΩ resistor to ground enables open thermocouple detection and proper grounding of the thermocouple. The sense pin should be connected to the output pin of the AD8495. Decoupling capacitors should be used to ensure clean power supply voltages on +VS and, if using dual supplies, on −VS, also. A 0.1 μF capacitor should be placed as close as possible to each AD8495 supply pin. A 10 μF tantalum capacitor can be used farther away from the part and can be shared.
Figure 4 Connection for AD8495
Figure 5 Connection for AD8495
2D-VIEW AND FOOTPRINT
Figure 6 2-D View and PCB Footprint of AD8495ARMZ
AD8495 RELATED PRODUCTS PRICE
Parts Mfr. Description Stock Prices Buy Now
AD8495ARMZ Analog IC THERMOCOUPLE A W/COMP 8MSOP 26894 $2.390 Lowest 
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AD8495ARMZ DATASHEET PDF