An implantable pumping system for pumping a fluid in an implantable gastric banding system comprises a pump for pumping the fluid. A voltage source provides a pump voltage to the system, and a voltage control circuit increases or decreases the pump voltage. A pump driver applies the pump voltage to the pump at a phase and a frequency. The implantable pumping system comprises a sensor that monitors a parameter to facilitate adjusting at least one of the phase or the frequency to maintain a desired value of the parameter. The parameter is associated with at least one of the implantable pumping system or the implantable gastric banding system. A micro controller is configured to manipulate at least one of the phase or the frequency to maintain the desired value of the parameter. The sensor may comprise a temperature sensor, a pressure sensor, and/or a flow rate sensor.