A circuit is disclosed that comprises a controller and an analog to digital converter (ADC) coupled to controller. The speed and/or the resolution of the ADC is configurable to provide optimum performance during the operation of the ADC. In an embodiment a wireless receiver with an adaptively configurable ADC for is provided. The speed and resolution the ADC is configurable depending on the operational mode of the receiver. Accordingly, through the use of an adaptively configurable ADC, power consumption and speed is optimized for each operational mode.