Instrumentation amplifier using fully-differential linear ota

The present invention relates to an instrumentation amplifier using a fully-differential linear operational transconductance amplifier (OTA), which comprises: an OTA outputting a first output current and a second output current with a first voltage and a second voltage as inputs an operational amplifier having a negative terminal connected to a first current output end outputting the first output current and a positive terminal connected to a second current output end outputting the second output current; a first resistor having one end connected between the second current output end and the positive terminal of the operational amplifier and the other end being grounded; and a second resistor having one end connected between the first current output end and the negative terminal of the operational amplifier and the other end connected to an output end of the operational amplifier. According to the present invention, the instrumentation amplifier has a simple circuit configuration, does not need matching of the resistors, and can adjust offsets by controlling gains with two resistors.