A feedback signal generator is an electronic device used to solve problems associated with closing feedback control loops. They are typically used to control devices like optocouplers incorporating elements like a shunt voltage regulator, an error amplifier, and a transconductance amplifier that may drive an optocoupler. They can also be programmed devices that are used to control the output voltage of DC-to-DC converters. Such devices may output a DC current proportional to a programmed value that drives the feedback node of a regulator. By changing the value, voltage of the regulator can be set by the user.

Isolated feedback generators are a special category of this device utilized when the control loop crosses an isolation boundary. They are an alternative to an optocoupler-based system, using small, low cost high-frequency isolation RF transformers. To enable this method of isolated signal transfer, the device modulates the feedback loop signal on an RF carrier.  Some devices also feature a clock input that enables synchronization to system clocks or the switching frequency of the switch-mode being controlled.

Feedback controllers can incorporate loop status monitoring to detect fault or range issues. They are usually specified with a percentage accuracy associated with the feedback process. Feedback signal generators usually operate at up to a 5MHz carrier frequency and may have an integrated RF oscillator and precision voltage reference.