Configurable logic cell for field programmable gate array - has device for performing combinational logic function coupled to device which is set to operate as D=type or toggle flip=flop

摘要

The logic cell (1) has inputs (4) and at least one output (5). The logic cell includes a device (2), e.g. a look-up table, whose inputs are connected to the inputs (4) of the logic cell. A second device (3), a flip-flop, has its single input connected to the output of the first device and its output coupled to the logic cell output terminal. The first device performs a desired combinational logic function. The second device stores a data value and can be set to operated either as a D-type flip-flop or as a toggle flip-flop. ADVANTAGE - Simplifies circuit for realising sequential logic, e.g. for counter or state machine.