Patent ID: 8941428
Filing Date: 2015-01-27
Classification: G11C,H03K

Abstract:
1. A flip flop comprising a first latching circuit and a second latching circuit, each of said first latching circuit and said second latching circuit for receiving and holding a data value, and each of said first latching circuit and said second latching circuit comprising: a feedback loop comprising two inverting devices arranged in a feedback loop, an output of a first inverting device being connected to an input of a second inverting device at a first portion of said feedback loop, said first portion holding said data value and an output of said second inverting device being connected to an input of said first inverting device at a second portion of said feedback loop, said second portion holding a complementary data value; a first input for receiving a data value; an output for outputting a value indicative of said data value from said feedback loop; a clock signal input for receiving a clock signal; an access control device configured to connect or isolate said first input from said first portion of said feedback loop in dependence upon a value of said clock signal; wherein said feedback loop comprises two switching circuits arranged in parallel at one of said first or said second portion of said feedback loop, said switching circuits being configured such that one of said switching circuits provides a connection between said inverting devices at said one of said first or second portion of said feedback loop, while an other of said second or first portion comprises a conducting element providing a permanent connection between said inverting devices; each of said latching circuits comprises control signal circuitry configured to provide at least one control signal to control said two switching circuits, said two switching circuits and said control signal circuitry being configured such that in response to said at least one control signal one of said two switching circuits is on and provides said connection between said inverting devices and said other of said two switching circuits is off; wherein said control signal circuitry is configured to provide said at least one control signal in dependence upon said data value such that in response to said data value changing said at least one control signal changes and one of said two switching devices that is currently on changes to said other of said two switching devices and said switching device that turns on and said access control device act together to update said data value within said feedback loop, wherein said output of said first latching circuit is connected to said first portion of said feedback loop and is configured to output said data value and said access control device of said second latching circuit is connected to said output of said first latching circuit, and said access control device of said first latching circuit and said access control device of said second latching circuit are configured to operate on different phases of said clock cycle such that one is open when the other is closed.