US Patent 7495473 Non-volatile look-up table for an FPGA

A non-volatile-memory-transistor based lookup table for an FPGA includes a n:1 multiplexer. A non-volatile memory transistor is coupled to each of the n inputs of the multiplexer. The multiplexer has x address inputs wherein 2x=n as is known in the art. The output of the multiplexer is coupled to Vcc through a pullup transistor. The gate of the pullup transistor is coupled to the output of an address transition detector circuit that has inputs coupled to the address inputs of the multiplexer. A sense amplifier is coupled to the output of the multiplexer.