The transimpedance amplifier presents a low impedance to the sensor and isolates it from the output voltage of the operational amplifier. In its simplest form (Fig. 1), a transimpedance amplifier is just an opamp with a large-valued feedback resistor, R f.OverviewIn, a transimpedance amplifier (TIA) is a to converter, almost exclusively implemented with one or more (opamps). The TIA can be used to amplify the current output of In the circuit shown in Figure 1, a sensor (represented as a current source) such as a photodiode is connected between ground and the inverting input of the opamp. The other input of the opamp is also connected to ground,. The frequency response of a transimpedance amplifier is inversely proportional to the gain set by the feedback resistor. The sensors which transimpedance amplifiers are used with usually hav.