Abstract: Auto-detection of audio formats is provided by using an auto-detect element to exploit differences among multiple formats to output a format select signal corresponding to the input to the auto-detect element. In a preferred embodiment, edge detection circuitry and a time counter are employed to recognize multiple audio formats automatically. The format select signal output from the auto-detect element is output to a multiplexer, or other switching means for switching among multiple input formats, so that the correct input signal processing is used. The auto-detect element removes the need for an external hardware select pin, thereby reducing the number of input pins to the circuit.

Abstract: For a system having multiple sources of digital input data to be converted to analog by Digital to Analog Converters (DACs), pre-processing of the multiple sources of data is provided, such that differences in input sampling rates are accommodated. When multiple digital input sources are to be converted to analog signals in a single integrated circuit, these input signals are routed to a clock generator having Phase Locked Loop (PLL) circuitry and to respective Asynchronous Sample Rate Converters (ASRCs). Sample rate information relating to an input signal selected from among the multiple input signals is determined during a locking operation of the PLL. Based on the common clock output from the clock generator, the ASRCs convert the input signals to a single sampling rate. Once the multiple input sources are converted to a common sample rate by the ASRCs, the inputs are converted to analog signals by DACs using the common clock and are output by the single Integrated Circuit.