Abstract: An IC includes first-third power rails over a semiconductor substrate. The first rail has a first polarity different from the second and third rails. The IC includes multiple first cells on the semiconductor substrate in first and second rows. The first row is separated from the second row by the first power rail. Each first cell includes a first height and a first structure having at least one transistor. For each first cell in the first row, the first structure is entirely between the first and second rails. Further, for each first cell in the second row, the first structure is between the first and third rails. The IC includes an extension cell arranged on the semiconductor substrate in the first row. The extension cell includes a second structure having at least one transistor. A portion of the second structure extends into the second row.

Abstract: An IC includes first-third power rails. The first-third power rails are located along corresponding first-third centerlines spaced apart by the same distance. A plurality of first logic cells is in first and second width that is an integer multiple of a unit width and a first semiconductor structure that includes multiple transistors. For each first logic cell in the first row, the first semiconductor structure is located entirely between the first and second centerlines. For each first logic cell in the second row, the first semiconductor structure is located entirely between the first and third centerlines. A multi-height logic cell includes a second height that is greater than the first height, and a second width that is at least the unit width. The second semiconductor structure includes at least two transistors. The second semiconductor structure is partially between the first and second centerlines and between the first and third centerlines.

Abstract: An integrated circuit, and method of forming the same. The integrated circuit includes standard logic cells and a combined logic cell over a semiconductor substrate. Each standard logic cell includes a standard height, a width that is an integer multiple of a unit width, first and second power rails, and at least one transistor and interconnections configured to implement a logic function that produces a single logic output. The combined logic cell includes the standard height, a width that is an integer multiple of the unit width, the first and second power rails, and at least two transistors and interconnections configured to implement a first logic function and a second logic function. The first and second logic functions produce first and second logic outputs, respectively. The interconnections are configured to direct the first logic output and the second logic output to destinations outside the combined logic cell.

Abstract: An integrated circuit, and method of forming the same. The integrated circuit includes standard logic cells and a combined logic cell over a semiconductor substrate. Each standard logic cell includes a standard height, a width that is an integer multiple of a unit width, first and second power rails, and at least one transistor and interconnections configured to implement a logic function that produces a single logic output. The combined logic cell includes the standard height, a width that is an integer multiple of the unit width, the first and second power rails, and at least two transistors and interconnections configured to implement a first logic function and a second logic function. The first and second logic functions produce first and second logic outputs, respectively. The interconnections are configured to direct the first logic output and the second logic output to destinations outside the combined logic cell.

Abstract: A flip-flop having first and second shared transistors. The flip-flop including a tri-state inverter and a master latch configured to receive an output of the tri-state inverter. The flip-flop also having a slave latch coupled to the master latch, the slave latch including a slave tri-state inverter. The flip-flop further having an output inverter coupled to receive one of an output of the slave latch and an output of the master latch and configured to generate a flip-flop output. The first shared transistor configured to receive a clock signal and having a drain terminal coupled a first transistor in the tri-state inverter and a second transistor in the slave tri-state inverter. The second shared transistor configured to receive an inverted clock signal and having a drain terminal coupled a third transistor in the tri-state inverter and a fourth transistor in the slave tri-state inverter.

Abstract: Examples of compact, high performance full adder circuits and methods of forming and operating the same are provided. In an example, a full adder comprises a first stage, a second stage and a third stage. The first stage has a first output at which a first reused signal is generated and a second output at which a second reused signal is generated. The second stage has a first reused signal input to which the first reused signal is applied, a second reused signal input to which the second reused signal is applied, and a sum output at which a sum signal is generated. The third stage has a third reused signal input to which the first reused signal is applied, a fourth reused signal input to which the second reused signal is applied, and a carry-out output at which a carry-out signal is generated. In some examples, the first stage includes a transistor stack and an inverter that share a transistor.

Abstract: A flip-flop having first and second shared transistors. The flip-flop including a tri-state inverter and a master latch configured to receive an output of the tri-state inverter. The flip-flop also having a slave latch coupled to the master latch, the slave latch including a slave tri-state inverter. The flip-flop further having an output inverter coupled to receive one of an output of the slave latch and an output of the master latch and configured to generate a flip-flop output. The first shared transistor configured to receive a clock signal and having a drain terminal coupled a first transistor in the tri-state inverter and a second transistor in the slave tri-state inverter. The second shared transistor configured to receive an inverted clock signal and having a drain terminal coupled a third transistor in the tri-state inverter and a fourth transistor in the slave tri-state inverter.

Abstract: A flip-flop having first and second shared transistors. The flip-flop including a tri-state inverter and a master latch configured to receive an output of the tri-state inverter. The flip-flop also having a slave latch coupled to the master latch, the slave latch including a slave tri-state inverter. The flip-flop further having an output inverter coupled to receive one of an output of the slave latch and an output of the master latch and configured to generate a flip-flop output. The first shared transistor configured to receive a clock signal and having a drain terminal coupled a first transistor in the tri-state inverter and a second transistor in the slave tri-state inverter. The second shared transistor configured to receive an inverted clock signal and having a drain terminal coupled a third transistor in the tri-state inverter and a fourth transistor in the slave tri-state inverter.

Abstract: A flip-flop having first and second shared transistors. The flip-flop including a tri-state inverter and a master latch configured to receive an output of the tri-state inverter. The flip-flop also having a slave latch coupled to the master latch, the slave latch including a slave tri-state inverter. The flip-flop further having an output inverter coupled to receive one of an output of the slave latch and an output of the master latch and configured to generate a flip-flop output. The first shared transistor configured to receive a clock signal and having a drain terminal coupled a first transistor in the tri-state inverter and a second transistor in the slave tri-state inverter. The second shared transistor configured to receive an inverted clock signal and having a drain terminal coupled a third transistor in the tri-state inverter and a fourth transistor in the slave tri-state inverter.

Abstract: At least some embodiments are directed to a flip-flop that comprises a tri-state inverter and a master latch coupled to the tri-state inverter and comprising a first transistor, a first inverter, and a first logic gate. The master latch receives a clock signal. The flop also comprises a slave latch coupled to the master latch and comprising a second transistor and a second inverter. The slave latch receives the clock signal. The flop further comprises an enablement logic coupled to the master latch and comprising multiple, additional logic gates. The tri-state inverter, the master and slave latches, and the enablement logic are configured so that when a flip-flop input signal D and a flip-flop output signal Q are identical and the clock signal is toggled, a state of the master latch and a state of the slave latch remain static.

Abstract: At least some embodiments are directed to a flip-flop that comprises a tri-state inverter and a master latch coupled to the tri-state inverter and comprising a first transistor, a first inverter, and a first logic gate. The master latch receives a clock signal. The flop also comprises a slave latch coupled to the master latch and comprising a second transistor and a second inverter. The slave latch receives the clock signal. The flop further comprises an enablement logic coupled to the master latch and comprising multiple, additional logic gates. The tri-state inverter, the master and slave latches, and the enablement logic are configured so that when a flip-flop input signal D and a flip-flop output signal Q are identical and the clock signal is toggled, a state of the master latch and a state of the slave latch remain static.

Abstract: At least some embodiments are directed to a flip-flop that comprises a tri-state inverter and a master latch coupled to the tri-state inverter and comprising a first transistor, a first inverter, and a first logic gate. The master latch receives a clock signal. The flop also comprises a slave latch coupled to the master latch and comprising a second transistor and a second inverter. The slave latch receives the clock signal. The flop further comprises an enablement logic coupled to the master latch and comprising multiple, additional logic gates. The tri-state inverter, the master and slave latches, and the enablement logic are configured so that when a flip-flop input signal D and a flip-flop output signal Q are identical and the clock signal is toggled, a state of the master latch and a state of the slave latch remain static.

Abstract: At least some embodiments are directed to a flip-flop that comprises a tri-state inverter and a master latch coupled to the tri-state inverter and comprising a first transistor, a first inverter, and a first logic gate. The master latch receives a clock signal. The flop also comprises a slave latch coupled to the master latch and comprising a second transistor and a second inverter. The slave latch receives the clock signal. The flop further comprises an enablement logic coupled to the master latch and comprising multiple, additional logic gates. The tri-state inverter, the master and slave latches, and the enablement logic are configured so that when a flip-flop input signal D and a flip-flop output signal Q are identical and the clock signal is toggled, a state of the master latch and a state of the slave latch remain static.

Abstract: At least some embodiments are directed to a flip-flop that comprises a tri-state inverter and a master latch coupled to the tri-state inverter and comprising a first transistor, a first inverter, and a first logic gate. The master latch receives a clock signal. The flop also comprises a slave latch coupled to the master latch and comprising a second transistor and a second inverter. The slave latch receives the clock signal. The flop further comprises an enablement logic coupled to the master latch and comprising multiple, additional logic gates. The tri-state inverter, the master and slave latches, and the enablement logic are configured so that when a flip-flop input signal D and a flip-flop output signal Q are identical and the clock signal is toggled, a state of the master latch and a state of the slave latch remain static.

Abstract: A full adder is disclosed that utilizes low area. The full adder includes an exclusive NOR logic circuit. The exclusive NOR logic circuit receives a first input and a second input. A first inverter receives an output of the exclusive NOR logic circuit and generates an exclusive OR output. A carry generation circuit receives the output of the exclusive NOR logic circuit, the exclusive OR output and a third input. The carry generation circuit generates an inverted carry. A second inverter is coupled to the carry generation circuit and generates a carry on receiving the inverted carry. A sum generation circuit receives the output of the exclusive NOR logic circuit, the exclusive OR output and the third input. The sum generation circuit generates an inverted sum. A third inverter is coupled to the sum generation circuit and generates a sum on receiving the inverted sum.

Abstract: A flip-flop is disclosed that utilizes low area. The flip-flop includes a tri-state inverter that receive a flip-flop input, a clock input and an inverted clock input. A master latch receives an output of the tri-state inverter. The master latch includes a common inverter. A slave latch is coupled to the master latch. The common inverter is shared between the master latch and the slave latch. An output inverter is coupled to the common inverter and generates a flip-flop output.

Abstract: The disclosure provides a flip-flop that utilizes low power as a result of reduced transistor count. The flip-flop includes a tri-state inverter that receives a flip-flop input and a clock input. A master latch is coupled to an output of the tri-state inverter and provides a control signal to the tri-state inverter. The control signal activates the tri-state inverter. A slave latch receives an output of the master latch and the control signal. An output inverter is coupled to an output of the slave latch and generates a flip-flop output.

Abstract: A full adder is disclosed that utilizes low area. The full adder includes an exclusive NOR logic circuit. The exclusive NOR logic circuit receives a first input and a second input. A first inverter receives an output of the exclusive NOR logic circuit and generates an exclusive OR output. A carry generation circuit receives the output of the exclusive NOR logic circuit, the exclusive OR output and a third input. The carry generation circuit generates an inverted carry. A second inverter is coupled to the carry generation circuit and generates a carry on receiving the inverted carry. A sum generation circuit receives the output of the exclusive NOR logic circuit, the exclusive OR output and the third input. The sum generation circuit generates an inverted sum. A third inverter is coupled to the sum generation circuit and generates a sum on receiving the inverted sum.

Abstract: A flip-flop is disclosed that utilizes low area. The flip-flop includes a tri-state inverter that receive a flip-flop input, a clock input and an inverted clock input. A master latch receives an output of the tri-state inverter. The master latch includes a common inverter. A slave latch is coupled to the master latch. The common inverter is shared between the master latch and the slave latch. An output inverter is coupled to the common inverter and generates a flip-flop output.

Abstract: The disclosure provides a flip-flop that utilizes low power as a result of reduced transistor count. The flip-flop includes a tri-state inverter that receives a flip-flop input and a clock input. A master latch is coupled to an output of the tri-state inverter and provides a control signal to the tri-state inverter. The control signal activates the tri-state inverter. A slave latch receives an output of the master latch and the control signal. An output inverter is coupled to an output of the slave latch and generates a flip-flop output.