operational amplifier

[sona]

An operational amplifier, often called an op-amp , is a DC-coupled
high-gain electronic voltage amplifier with differential inputs and,
usually, a single output. Typically the output of the op-amp is
controlled either by negative feedback, which largely determines the
magnitude of its output voltage gain, or by positive feedback, which
facilitates regenerative gain and oscillation. High input impedance at
the input terminals and low output impedance are important typical
characteristics.


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