In electronics, a transimpedance amplifier (TIA) is a current to voltage converter, almost exclusively implemented with one or more operational amplifiers (opamps). It's also a common building block that helps explain the performance and stability limits of many other op-amp circuits. TIAs present a low-impedance input for current-output sensors such as photodiodes, preserving linear conversion and bandwidth. Vout = − Iin × Rf. A general-purpose current-measurement system employs a current transformer, ac-coupled to a transimpedance amplifier. About transimpedance and transconductance: The words "transconductance" and "transimpedance" are often used interchangeably. At its simplest, it's an operational amplifier with a feedback resistor, and the output voltage follows Ohm's law: V_out = I × R_F, where I is the input current and R_F is the feedback.
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