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The AD623 only requires a resistor to sets its gain value and hence can be easily set up. A very basic commonly used circuit for the AD623 is shown below.

The IC is powered using the pin 7 and pin 4, here I have used a singly supply of +5V hence the pin 4 is grounded. If a dual supply voltage is used the pin 4 will be provided with negative voltage. The non - inverting pin (pin 2) and the inverting pin (pin 3) is connected the signal which has to be amplified or compared base on the application of the Op-Amp. The Reference pin (pin 5) is normally grounded along with pin 4, the reference pin is used to direct the output towards a voltage when the difference voltage between the inverting and the non-inverting pin is 0V.

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Alternatively you can also use the chart below which has the value of resistor and standard gain values listed.

With no external resistor, the AD623 is configured for unity gain (G = 1), and with an external resistor, the AD623 can be programmed for gains of up to 1000.

DKARDU AD623 Millivolt Voltage Amplifier Module

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