Abstract: A voltage detector including a voltage following circuit connected to a power supply and operable to follow a voltage value of the power supply, a selectable threshold point circuit connected to the voltage following circuit and operable to select one of a plurality of values for a threshold point of the power supply, and a switch circuit coupled to the selectable threshold point circuit and the voltage following circuit, the switch circuit cooperating with the selectable threshold point circuit to generate an output indicating whether the value of the power supply has increased above or decreased below the selected value for the threshold point in response to the followed value of the power supply.

Abstract: A low battery detect circuit with digitally programmable detect levels. The programmable low battery detect circuit includes a comparator that compares a stable reference voltage against a battery-supplied voltage as divided down by a digitally programmable resistive divider chain. By programmably varying the resistance of the divider chain, the low battery detect threshold level can be varied depending on the requirements of the application.

Abstract: A No-Fall-Through, FIFO memory includes a memory section comprising a plurality of locations for storing data words. Data words are written into the storage locations in response to a write clock input signal. Data words are read from the storage locations, in the same sequence as previously written, in response to a read clock signal. A write pointer maintains a write pointer value indicative of the number of data words which have been written. A read pointer maintains a read pointer value indicative of the number of data words which have been read. A comparator monitors the write pointer and read pointer values and detects differences between the two. The characteristics of the differences are utilized to control internal operations of the FIFO.