Abstract: Memory cell structures and related circuitry for use in non-volatile memory devices are described. The cell structures can be fabricated utilizing standard CMOS processes, e.g. sub 0.35 micron or sub 0.25 micron processes. Preferably, the cell structures can be fabricated using 0.18 micron or 0.15 micron standard CMOS processes. Advantageously, the cell structures can be programmed so that a conductive path is formed between like type materials. For example, in certain cell structures a cell is programmed by applying a programming voltage in such a way as to form a conductive path between a p-type gate and a p-type source/drain region or an n-type gate and an n-type source/drain region. Programming cells in this manner advantageously provides a programmed cell having a low, linear resistance after programming. In addition, novel charge pump circuits are provided that, in a preferred embodiment, are located “on chip” with an array of memory cells.

Abstract: An analog-to-digital converter (ADC) is realized in a field programmable gate array (FPGA) without adding special dedicated analog circuitry. In a digital application, a comparator in an interface cell of the FPGA compares an incoming digital signal to a reference voltage. Adjusting of the reference voltage allows the interface cell to support different digital I/O standards. In one embodiment, the comparator is not used for this digital purpose, but rather is used as a comparator in an ADC. A flash ADC is realized by using the comparators of numerous interface cells as the comparators of the flash ADC. Conversion speed is increased by reducing the impedance of the analog signal input path. An on-chip resistor string is provided so that the flash ADC can be realized without external components. In another embodiment, the comparator of the interface cell is the comparator of a successive approximation ADC.