Signals-From-Noise: Current Sources
by Dave Van Ess, Principal Application Engineer, MTS, Cypress Semiconductor

There are times when it is necessary to generate a precise current. It may be for some sensor that specifies a current stimulus. It may be a constant current source, or it may change as a function of some input voltage. A variable current source controlled by a voltage is sometimes referred to as a transconductance amplifier. Several different types of current sources are described here.

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