Flexible data rate handling in data bus receiver

The present invention relates to a receiver circuit for processing an incoming bit stream from a bus system. The circuit comprises an analog interface for converting the analog signal to a digital input data stream. The interface comprises an analog filter and a switch to process the analog signal before generating the digital input data stream using the filter if, and only if, a selection criterion controlling the switch is met. The circuit comprises a frame decoding unit for decoding a data frame encoded in the digital input data stream in accordance with a CAN protocol, and a frame processing unit that comprises a flexible data rate detector and a recessive bit counter for counting consecutive recessive bits after detecting the flexible data rate frame. The selection criterion is satisfied when the flexible data rate frame is detected and unsatisfied when the recessive bit counter reaches a predetermined number.