Method and apparatus to select a parameter/mode based on a measurement during an initialization period

Abstract

Techniques are disclosed to select functional parameters and/or operating modes of a circuit based on a measurement during an initialization period. In one aspect an integrated circuit includes a threshold detection circuit coupled to measure during an initialization period of the integrated circuit a signal from a first external circuit comprising one or more components coupled to a first external terminal of the integrated circuit. A selection circuit is coupled to the threshold detection circuit to select a parameter/mode of the integrated circuit in response to the signal from the first external circuit during the initialization period of the integrated circuit. The first external terminal is further coupled to one or more additional external circuits, each of which comprising one or more components. The one or more additional external circuits are coupled to provide one or more signals at the first external terminal to be used by the integrated circuit during normal operation at times other than the initialization period to provide at least one additional function for the integrated circuit after the initialization period of the integrated circuit is complete.