US Patent 7576568 Self-selecting precharged domino logic circuit

A domino logic circuit having an input terminal and a precharge node. A first switch is responsive to a second switch sensing one of a high or low voltage at the precharge node to charge the precharge node and the second switch is responsive to the one of a high or low voltage at the precharge node to control the first switch charging the precharge node. The first switch is preferably a p-channel transistor and the second switch is preferably an n-channel transistor. The circuit also includes an output terminal, an inverter coupled between the precharge node and the output terminal and feedback circuitry coupled between the output terminal and coupled to the second switch to provide the charge state of the precharge node to the second switch. The circuit further includes a pair of transistors having serially connected current paths, the serially connected current paths being coupled between the precharge node and a reference source.