LOGIC GATE BASED ON INVALIDATED LATCHING

摘要

PROBLEM TO BE SOLVED: To provide a pre-charge circuit that latches an output based on a logical input for transition from a pre-charge state to an evaluation state. SOLUTION: This invention provides the pre-charge circuit that has a 1st pre-charged node, a 2nd pre-charged node and a latch device. The 1st pre- charged node is charged to a high level for a pre-charge state. The 1st pre- charged node is discharged to a low level or remains to be charged at a high level in response to the transition from the pre-charge state to the evaluation state. The 2nd pre-charged node in the evaluation state has a value based on d a value of the 1st pre-charged node at the transition of the circuit to the evaluation state. The latch device is connected to the 2nd pre-charged node and latches the value in the evaluation state. The 1st pre-charged node does not affect this value by the latch device when the circuit is once sufficiently transited to the evaluation state.