Self-configuring input buffer on flash memories

This invention relates to systems including nonvolatile writeable memory. More particularly, this invention relates to interfacing a nonvolatile writeable memory device to an electronic system application. A low-power input buffer for a nonvolatile writeable memory is described. The low-power input buffer accepts input signals having one of a number of pairs of logic levels. The low-power input buffer provides output signals having a pair of logic levels that may differ from the logic levels of the input signal. The low-power input buffer comprises an inverter that receives an input signal, a circuit with a relatively low voltage drop, and a feedback pull-up device. The circuit with the relatively low voltage drop causes the low-power input buffer to accept input signals having one pair of logic levels while providing signals that may have a different pair of logic levels. The feedback pull-up device prevents the low-power input buffer from drawing leakage current. The low-power input buffer is coupled to the nonvolatile writeable memory and coupled to the same power supply output as the nonvolatile writeable memory. The low-power input buffer uses input signals having logic levels compatible with complementary metal-oxide semiconductor (CMOS) technology.