LCELL Primitive
The LCELL buffer allocates a logic cell for the project. The LCELL buffer produces the true and the complement of a logic function and makes both available to all logic in the device. (The output of the LCELL buffer must feed through a NOT gate to use the complement of the logic function.)
An LCELL buffer always consumes one logic cell. It is not removed from a project during logic synthesis.
Note: Do not use LCELL primitives to create an intentional delay or
asynchronous pulse. The delay of these elements varies with temperature, power supply
voltage, and device fabrication process, so race conditions can occur and create an
unreliable circuit.
You can turn on the Implement as Output of Logic Cell logic option to insert LCELL buffers at strategic points in the project logic. When you turn on the Ignore LCELL Buffers logic option, the Compiler automatically converts all LCELL buffers to WIRE primitives.
Note: For information about Quartus® Prime primitive instantiation, go to Using a Quartus® Prime
Logic Function.