The servo amplifier is the link between the controller and motor. Their job is to translate the low energy reference signals from the controller into high energy power signals to the motor. Servo amplifiers are available to control the speed and position of both brush and brushless motors. Today these units can be expected to handle all of the system feedback including encoders, resolvers and tachometers, as well as limit switches and other sensors. Servo amplifiers are also being asked to close the torque loop, velocity loop and position loop and being given the responsibility of path generation. By taking on mServo amplifiers are taking on many of the more complex control functions that used to be the sole domain of the controller.