Abstract: Methods and apparatus are provided for time-balanced switching of multiplexer circuits. An embodiment of the invention includes a transistor chain coupled to the output of the multiplexer circuit. The transistor chain preferably delays transitions that would otherwise occur relatively quickly, to match the timing of transitions that occur relatively slowly. The timing of relatively slow transitions is left unaltered. The invention advantageously allows all selector input transitions to yield a data output transition with a substantially constant delay.

Abstract: The present invention provides an adaptive keeper circuit to control Domino Logic Dynamic Circuits using Rate Sensing Technique to provide reduced contention and efficient process tracking at given noise robustness with less overhead in area, power and delay, said adaptive keeper comprising, keeper PMOS transistor (M1), wherein the drain of M1 is connected to wide AND-OR logic circuit; the rate controller consisting of reference rate transistor (M4), feedback PMOS transistor (M2), feedback shutoff transistor (M5), clock shutoff transistor (M6), pre-charge PMOS transistor (M3), wherein the input of the rate controller is directly connected to drain of the keeper PMOS (M1) and the output of the rate controller is directly connected to the gate of the PMOS keeper (M1).

Abstract: To pre-charge a node to one of first and second voltage levels in response to inputs received at the corresponding voltage level, to selectively level shift the node from the first voltage level to the second voltage level when in a first voltage mode, and to maintain the node at the second voltage level when in a second voltage mode. Level shifting from first voltage level may be performed within one gate stage that may be bypassed when in the second voltage mode. The node may be discharged with no delay difference between the first and second voltage modes. Inputs may include a clock signal, which may be received at either of the first and second voltage levels without level shifting the clock signal. A circuit may be implemented with a multi-core processor system to permit selective voltage mode operation of the cores.

Abstract: A power gating circuit includes a logic circuit, a switching element and a retention flip-flop. The logic circuit is coupled between a first power rail and a virtual power rail. The switching element selectively couples the virtual power rail to a second power rail in response to a mode control signal indicating an active mode or a standby mode. The retention flip-flop selectively performs a flip-flop operation or a data retention operation in response to a voltage of the virtual power rail.

Abstract: A method and an apparatus for obtaining an equivalent circuit model of a multi-layer circuit are disclosed. The method includes simulating the multi-layer circuit using an electromagnetic field analysis to provide a coupling network; and simplifying the coupling network using a circuit model order reduction method to generate the equivalent circuit model. The method is very simple to implement and the equivalent circuit model obtained has an apparent physical meaning.

Abstract: A semiconductor device according to the present invention comprises a first semiconductor integrated circuit 11 having a predetermined function, the first semiconductor integrated circuit outputting a required output signal, a second semiconductor integrated circuit 12 in which a plurality of MOS elements (PMOS transistor or NMOS transistor) for independently switching to and from a conducted state and a non-conducted state in accordance with a plurality of gate signals each having a different timing is provided and the plurality of MOS elements is connected in parallel to an output or an input of the first semiconductor integrated circuit, and a pulse generating circuit 13 for generating and outputting the plurality of gate signals ?i (i=1, 2, 3) each having a different timing with respect to the plurality of MOS elements in the second semiconductor integrated circuit.

Abstract: First circuitry is powered by a first power supply domain and provides a data signal referenced to the first power supply domain. Second circuitry is powered by a second power supply domain that differs from the first power supply domain. The data signal becomes referenced to the second power supply domain by a clocked level shifter that couples the first circuitry to the second circuitry and buffers the data signal from the first power supply domain to the second power supply domain by only using a single supply voltage. The clocked level shifter is clocked by a signal that is used to precharge a first node and a second node of the clocked level shifter until the data signal is valid for at least a setup time period. The first and second nodes are precharged to establish a known state in the clocked level shifter.

Abstract: Provided is a level shift circuit. The level shift circuit includes an inverter including a first transistor having a first polarity to which an input signal from an input port is applied through a gate and a second transistor having a second polarity which is an opposite polarity to the first polarity, the second transistor being connected in series to the first transistor between a positive source voltage and a negative source voltage and a connection node between the first and second transistors being an output port, a capacitor connected between a gate of the first transistor and a gate of the second transistor, and a voltage adjusting means for accurately adjusting a voltage applied to the gate of the second transistor according to an exact switching operation time of the second transistor, using a clock signal and an output port signal of the inverter. A stable and high-speed operation can be performed with a comparatively small size and low power consumption can be achieved.

Abstract: Apparatuses and methods are provided for a self-timed dynamic sense amplifier flop circuit, wherein a pulse generating circuit may be adapted to generate at least a first logic signal based, at least in part, on a first evaluation node signal, and a discharge path circuit comprising at least a first transistor within a first stack of transistors may be operatively responsive to the first timing signal.

Abstract: Various systems and methods for implementing dynamic logic are disclosed herein. For example, some embodiments of the present invention provide dynamic logic devices with a logic circuit that includes an inverting output buffer, a logic function, a bias transistor, and a current circuit. An input of the logic function is electrically coupled to a logic input, an output of the logic function is electrically coupled to an input of the inverting output buffer, and the logic function exhibits a leakage current. The gate of the bias transistor is electrically coupled to an output of the inverting buffer, and a first leg of the bias transistor is electrically coupled to the input of the inverting buffer. The current circuit supplies a current corresponding to the to a second leg of the bias transistor. In some cases, an improved performance may be achieved for a given leakage, or a reduced leakage may be achieved for a given performance.

Abstract: A DFLOP circuit for an EAIC system includes a resolver. The resolver includes a signal transmission controller that is activated under the control of an internal clock signal to receive and transmit an input signal, and a precharge unit that is activated in response to the internal clock signal to precharge an output node of the signal transmission controller.

Abstract: Low voltage swing techniques are provided for simultaneously reducing the active and standby mode power consumption and enhancing the noise immunity in domino logic circuits. One or both the upper and lower boundaries of the voltage swing at the dynamic node may be different from the upper and lower boundaries of the voltage swing at the output node. Further, the domino logic circuit may use dual Vt thereby reducing the short-circuit current during operation. Meanwhile, full voltage swing signals may be maintained at the inputs and outputs for high speed operation. The low swing circuit techniques are provided that modify the output voltage swing of a domino gate, thereby reducing the active mode power consumption.

Abstract: A buffer circuit includes first and second transistors which are connected in series between first and second power supplies and which are controlled to be on/off based on values of signals at their control terminals are provided, in which a connection point between the two transistors is connected to an output terminal (OUT) and a control terminal of the first transistor is connected to an input terminal (IN), and a control circuit for performing on/off control over the second transistor based on an input signal from the input terminal (IN).

Abstract: A novel methodology for the construction and operation of logical circuits and gates that make use of and contact to a fourth terminal (substrates/bodies) of MOSFET devices is described in detail. The novel construction and operation provides for maintaining such body-contacted MOSFET devices at a lower threshold voltage (VTh) when actively on (to increase overdrive and performance), and at a higher relative threshold voltage when off (to reduce leakage power). Because the threshold potential of a gate moves inversely to its body potential, it follows then that in general, the body of a given device must be tied to the inverse of the device's drain voltage to achieve such a desirable threshold potential modulation effect for improved device, circuit, gate and logical family operation.

Abstract: A method extends a clock-gating technique to provide a sleep signal for controlling switch circuits that reduce active leakage power. Using this extension of the clock-gating technique, fine-grained power-gating is achieved. The method automatically identifies, at an RTL or a gate level, the logic circuits that can be power-gated. The method of the present invention derives a sleep signal for fine-grained power-gating that may be applicable to both time-critical and non-time-critical designs.

Abstract: One aspect of the invention relates to a device including a first storage element and a first clock gating element, wherein a data input of the first storage element is coupled to an output of a combinatorial logic (CL) element, wherein the first storage element is clock-gated with the first clock gating element using a first clock enable signal to generate a clock signal for the first storage element, wherein the first clock enable signal is generated to suppress the clock signal in the first clock gating element when each of the at least one data input of the CL element is in a second quiescence inducing condition with respect to the clock signal at the same time as when each of the at least one control input of the CL element is in the first quiescence inducing condition.

Abstract: A power saving clock-gating method and a power saving clock-gating circuit for implementing power savings in High Speed Serializer-deserializer (HSS) cores, and a design structure on which the subject circuit resides are provided. The power saving clock-gating circuit includes a clock gate signal used to initiate the starting and stopping of the C2 clocks. The clock gate signal is applied to a first latch of plurality of current-mode logic latches in a clock gate aligner block, which provides clock gate aligned signal to synchronously start a C2 clock generator. A power savings logic circuit generates a power down signal to turn off the plurality of current-mode latches and predefined clock buffers after the C2 clocks have been started, and then responsive to a changed state of the clock gate signal to turn on the predefined clock buffers and the plurality of current-mode logic latches to begin another synchronous start operation.

Abstract: A logic gate is constructed of an insulated gate field effect transistor (MIS transistor) having a thin gate insulation film. An operation power supply line to the logic gate is provided with an MIS transistor having a thick gate insulation film for switching the supply and stop of an operation power source voltage. A voltage of the gate of the power source switching transistor is made changing in an amplitude greater than an amplitude of an input and an output signal to the logic gate. Current consumption in a semiconductor device configured of MIS transistor of a thin gate insulation film can be reduced and an power source voltage thereof can be stabilized.

Abstract: An embodiment of the invention relates to a circuit for distributing an initial signal, comprising an input node receiving the initial signal, a plurality of terminal nodes each providing at least one resulting signal to a circuit component, and different connection branches between the input node and the plurality of terminal nodes, to which a plurality of intermediate nodes is connected, wherein connection branch is duplicated, so that each node among the input node and the intermediate nodes comprises two inputs and two outputs allowing double propagation of the initial signal towards the terminal nodes through duplicated connection branches, each terminal node terminal node receiving two input signals, images of the initial signal and providing the resulting initial signal: an image of the input signals if said input signals are identical, or inactive, if the input signals are different from each other.

Abstract: An elastic pipelined latch. The latch includes a control input for configuring the latch into a repeater state or a latch state, a drive component responsive to the control input and for driving an input signal through as an output signal, and a pulse width/inhibit component coupled to the drive component. The latch may further include a reset threshold component coupled to the drive component for inhibiting oscillation of the drive component, and/or a latch component for passing the present state of the input signal to the output signal when configured as the repeater state and for maintaining the previous state of the output signal during transitions of a clock signal when configured as the latch state.

Abstract: A programmable clock generator circuit receives control signals and a global clock and generates a pulsed data clock and a scan clock in response to gating signals. The clock generator has data clock and scan clock feed-forward paths and a single feedback path. Delay control signals program delay elements in the feedback path and logic gates reshape and generate a feedback clock signal. The global clock and the feedback clock signal are combined to generates a pulsed local clock signal. A scan clock feed-forward circuit receives the local clock and generates the scan clock. A data clock feed-forward circuit receives the local clock and generates the data clock with a logic controlled delay relative to the local clock signal. The feedback clock is generated with controlled delay thereby modifying the pulse width of the data and scan clocks independent of the controlled delay of the data clock feed-forward path.

Abstract: Disclosed herein is a digital system that includes a distribution network to carry a reference clock, and a circuit domain coupled to the distribution network to receive the reference clock for synchronous operation in accordance with the reference clock. The circuit domain includes a clock generator driven by the reference clock to generate a resonant clock signal, an input port to receive a control signal, and a gate coupled to the input port to discontinue application of the resonant clock signal within the circuit domain based on the control signal.

Abstract: A system and method for hardening dynamic logic against single event upset is described. A precharge circuit is hardened and then connected to two pull down networks. The two pull down networks are redundant and, under normal operating conditions, provide substantially the same outputs when receiving substantially the same inputs. The two outputs are then voted to provide an output that is hardened against single event upset. Alternatively, the two outputs may be connected to a next stage of dynamic logic circuits or other circuitry for evaluation.

Abstract: A circuit incorporating a current starved ring oscillator is coupled to a power gate switch in an integrated circuit. The circuit incorporating the current starved ring oscillator amplifies a voltage difference between a virtual ground associated with the power gate switch and ground, and converts the difference to a frequency. Digital logic monitors the output of the ring oscillator using a counter and a reference clock. Control circuitry controls operation of the integrated circuit in dependence on the monitored conditions associated with the power gate switch. A method monitors a virtual ground voltage across a power gate switch in an integrated circuit; and controls operation of the integrated circuit in dependence on the monitored virtual ground voltage.

Abstract: In a dual rail domino circuit 3 using a combination of a domino circuit 1 for outputting positive logic and a domino circuit 2 for outputting negative logic, an AND 4 and a NAND 5 as members for simultaneously fixing an output of the domino circuit 1 and an output of the domino circuit 2 at a low level in an evaluation phase are provided, and a logical AND of a gating control signal and an input signal is inputted to the domino circuit 1 and a logical NOT of the logical AND of the gating control signal and the input signal is inputted to the domino circuit 2.

Abstract: A voltage regulator and method of voltage regulation for a power-on reset condition are described. Voltage regulation control signals responsive to the power-on reset condition are obtained. The control signals are generated with a first voltage to be associated with a second voltage to provide a first power-on-reset signal and a second power-on-reset signal which are opposite in state to one another. A portion of driver logic is tri-stated responsive to the control signals, and the second power-on-reset signal to at least impede supply to supply current leakage. Voltage is pulled up on a first output port and a second output port of the driver logic responsive to the first power-on-reset signal. A portion of a semiconductor substrate is electrically coupled to a higher one of a first voltage and a second voltage responsive to the pulling up to at least further impede the supply to supply current leakage.

Abstract: A voltage supply control circuit is arranged between a true ground voltage and a pseudo ground line. In an active mode, first and second control signals are at the “H” and “L” levels, respectively. In response to this, a first switch is turned on so that a first node is electrically coupled to a power supply voltage, and attains the “H” level. Further, a second switch is turned on to couple electrically the ground voltage to a second node. In a standby mode, the first and second control signals are at the “L” and “H” levels, respectively. In response to this, a third switch is turned on to couple electrically the first and second nodes together. Since the power supply voltage was electrically coupled to the first node according to the turn-on of the first switch in the active mode, the path of the control signal including the first node to the switch has accumulated charged charges.

Abstract: A circuit includes a first transistor stack that receives an input signal, a voltage reference, a reference potential, a clock signal and an inverted clock signal, and generates an output signal that is an inverse of the input signal. A first inverter receives the output signal from the first transistor stack. A second transistor stack receives the voltage reference, the reference potential, the clock signal and the inverted clock signal, and generates an output signal that is an inverse of an output signal from the first inverter. A pass control circuit includes first and second transistors. The first terminals of the first and second transistors are coupled together and receive the output signal of the second transistor stack, control terminals of the first and second transistors receive the clock signal and the inverted clock signal, respectively, and second terminals of the first and second transistors are coupled together and output the output signal of the second transistor stack.

Abstract: Embodiments disclosed herein provide sleep mode solutions for retaining state information while reducing power in a logic block.

Abstract: An apparatus, system, and method are described for synchronously resetting logic circuits. A synchronous reset signal is coupled to at least one asynchronous reset input for synchronously resetting sequential logic. In one embodiment, reset logic generates a signal coupled to the at least one asynchronous reset input of the sequential logic to synchronously reset the sequential logic.

Abstract: A circuit comprises a first plurality of transistors of a first channel length disposed along a speedpath, the first plurality of transistors providing a first timing performance. The circuit also comprises a second plurality of transistors of a second channel length having an expected equivalent functionality as the first plurality of transistors and disposed in parallel with the first plurality of transistors along the speedpath, wherein the second channel length is different from the first channel length. In addition, the circuit comprises an element configured to selectively replace the first plurality of transistors with the second plurality of transistors in response to a determination that the first timing performance of the first plurality of transistors fails a timing requirement of the speedpath. In one embodiment, the second channel length is a sub-minimal geometry with respect to the first channel length.

Abstract: A clock gating system and method is disclosed. In a particular embodiment, the system includes an input logic circuit having at least one input to receive at least one input signal and having an output at an internal enable node. A keeper circuit includes at least one switching element that is responsive to a gated clock signal and is coupled to the internal enable node to selectively hold a logical voltage level at the internal enable node. The system further includes a gating element responsive to an input clock signal and to the logical voltage level at the internal enable node to generate the gated clock signal.

Abstract: A level shifter circuit and method of operating therefor. The level shifter circuit is coupled to receive a data signal via an input circuit, wherein the input circuit is in a first voltage domain. The level shifter circuit is also coupled to receive a clock signal from a second voltage domain. On a first portion of the clock cycle, true and complementary output nodes of the level shifter circuit (which are in the second voltage domain) are pulled to a first voltage by activation of respective pull transistors. On a second portion of the clock cycle, one of the true or complementary output nodes is pulled to a second voltage on a second voltage node by enabling the supply to the latch. Data is captured by the keeper, outputting true and complementary versions of the data signal in the second phase of the clock.

Abstract: An limited-switch dynamic logic (LSDL) circuit provides reduced power consumption by reducing clock power dissipation. By clocking LSDL gates with a clock signal having a reduced voltage swing in the evaluation phase, the LSDL gates are permitted to operate, while reducing the clock power consumption dramatically. Since clock power consumption dominates in LSDL circuits, the reduction in clock power dissipation results in a significant reduction in overall circuit power consumption. The reduced swing clock is produced at a plurality of local clock buffers by supplying the local clock buffers with an extra power supply rail that is switched onto the clock distribution lines by the local clock buffers in response to the full-swing evaluate phase clock received from the global clock distribution network by the local clock buffers.

Abstract: A clock gated circuit includes a clock signal receiving unit that applies a first voltage to a fighting node when the clock signal is at a first logic; a discharging unit that discharges an electric charge from the fighting node when the clock signal is transitioned from the first logic to a second logic and when the enable signal is activated; a voltage maintaining unit that maintains the fighting node at a power or ground voltage; and an output unit that inverts a logic level of the fighting node to generate the gated clock signal. A blocking unit can be included that blocks a power voltage from being provided to the fighting node by the voltage maintaining unit when discharging. A blocking transistor can be included that prevents unnecessary electric charge from inflowing into the fighting node to reduce power consumption and discharging time.

Abstract: Some embodiments provide dynamic circuits with dynamic nodes that may float during a disable mode to reduce leakage.

Abstract: An integrated circuit that includes a gate control voltage generator that supplies a current control gate voltage to a plurality of current control devices of a corresponding plurality of dynamic logic circuits each having a keeper circuit. The gate control voltage generator provides, via current control gate voltage, global control of the amount of keeper current flowing through the keeper circuits so as to enhance the performance of the dynamic logic circuits.

Abstract: A logic circuit includes a storage node coupled to a data line and a soft-error protection circuit to change a logical value of the storage node from a first value to a second value when the logical value of the storage node does not correspond a logical value of an output node. The logic circuit may be a set dominant latch and a memory circuit may be formed based on the set dominant latch.

Abstract: A number of logic state catching circuits are described which use a logic circuit with a first input, a second input, and an output. The logic circuit is configured to respond to a change in state of a data value coupled to the first input causing a representative value of the data value to be generated on the output. The second input receives a latched version of the data value to hold the representative value on the output after the data value has returned to its original state. A latching element is configured to respond to the change in state of the data value by latching the data value and to couple the latched version of the data value to the second input. A reset element is configured to respond to a change in state of a clock input by resetting the latching element.

Abstract: The present invention provides a latch circuit that is operable to generate a pulse from first and second clock signals to allow gates in a datapath to propagate data with minimal latency. The first clock signal is a version of the system clock and the second control signal is a time-shifted, inverted version of the system clock signal. Each of the individual latches in a datapath comprises data propagation logic. In one embodiment of the invention, the data propagation logic uses the first and second clock signals to generate an “implicit” pulse. In another embodiment of the invention, the data propagation logic uses the first and second clock signals to generate an “explicit” pulse. The implicit and explicit pulses are used to control the transmission gate of the latch to provide propagation of data through the latch with minimal latency.

Abstract: An output buffer for an IC includes a PMOS transistor having a source coupled to an operating voltage, and an NMOS transistor serially coupled between a drain of the PMOS transistor and a complementary operating voltage. A first driver is coupled to a gate of the PMOS transistor for selectively turning on or off the same. A second driver is coupled to a gate of the NMOS transistor for selectively turning on or off the same. A decoder is coupled to the first and second drivers for controlling the first driver or the second driver to turn on the PMOS transistor or the NMOS transistor at a high rate or a low rate in response to slew rate control signals indicating a slew rate control mode or a non-slew rate control mode.

Abstract: Leakage current reduction from a logic block is implemented via power gating transistors that exhibit increased gate oxide thickness as compared to the thin-oxide devices of the power gated logic block. Increased gate oxide further allows increased gate to source voltage differences to exist on the power gating devices, which enhances performance and reduces gate leakage even further. Placement of the power gating transistors in proximity to other increased gate oxide devices minimizes area penalties caused by physical design constraints of the semiconductor die.

Abstract: In a dynamic flip-flop circuit with a data selection function, for example, when data having an H value has been selected using a selection signal S0, a first node N1 is L and a second node N2 of a second dynamic circuit 1B is H, so that an output signal Q has an H level. In this case, when none of a plurality of pieces of data D0 to D2 is selected using selection signals S0 to S2, the first node N1 is H, so that the electric charge of the second node N2 is discharged and the output signal Q erroneously has an L level. However, in this case, an output node N3 is H and a fourth node N4 is L, so that an n-type transistor Tr6 of the second dynamic circuit 1B is turned OFF, thereby preventing the second node N2 from being discharged. Therefore, a normal operation is performed while securing a satisfactorily high-speed operation even when none of the pieces of data is selected.

Abstract: A design structure for a circuit that has a limited switch dynamic logic gate having a front end logic circuit and a latch. The output of the front end logic circuit is connected to an input of the latch, and the front end logic circuit evaluates a set of input signals applied to the front end logic circuit to generate an output signal. The latch receives and holds the output signal. The circuit also has a logic circuit having an output connected to a clock input in the front end logic circuit. The logic circuit generates a modified clock signal in response to receiving a clock signal from a clock source, and the modified clock signal has a duration that provides a minimum period of time for the front end logic to evaluate the set of input signals and generate the output signal.

Abstract: A circuit that has a limited switch dynamic logic gate having a front end logic circuit and a latch. The output of the front end logic circuit is connected to an input of the latch, and the front end logic circuit evaluates a set of input signals applied to the front end logic circuit to generate an output signal. The latch receives and holds the output signal. The circuit also has a logic circuit having an output connected to a clock input in the front end logic circuit. The logic circuit generates a modified clock signal in response to receiving a clock signal from a clock source, and the modified clock signal has a duration that provides a minimum period of time for the front end logic to evaluate the set of input signals and generate the output signal.

Abstract: Methods and apparatus are provided for time-balanced switching of multiplexer circuits. An embodiment of the invention includes a transistor chain coupled to the output of the multiplexer circuit. The transistor chain preferably delays transitions that would otherwise occur relatively quickly, to match the timing of transitions that occur relatively slowly. The timing of relatively slow transitions is left unaltered. The invention advantageously allows all selector input transitions to yield a data output transition with a substantially constant delay.

Abstract: Leakage currents at IC inputs can be avoided while the IC is disabled by providing a switch that is responsive to deactivation of an enable input to isolate functional circuitry of the IC from one of the power supply nodes of the IC. This eliminates power supply current while the IC is disabled. Further unwanted current flow can be avoided while the IC is disabled by providing a switch that is responsive to the enable input for selectively connecting and disconnecting the base of a reference voltage transistor to and from the transistor's grounded collector, which collector is defined by the substrate of the IC. Disconnection of the base from the grounded substrate/collector eliminates base current and thus prevents emitter-to-collector current flow through the transistor when the IC is disabled.

Abstract: A logic processing circuit including a plurality of flip-flop including a front stage flip-flop and a rear stage flip-flop, a logic gate circuit network adapted to process data stored in the front stage flip-flop, a result of the process being stored in the rear stage flip-flop, and switching means for switching between a power-on period and a power-off period, the power-on period being a period in which power is being provided to the logic gate circuit network, the power-on period corresponding to either a low-level state period of a clock signal or a high-level state period thereof, the power-off period being a period in which the power is being turned off, the power-off period corresponding to the state period other than the state period corresponding to the power-on period.

Abstract: In high-speed flip-flops and complex gates using the same, the flip-flop includes a first PMOS transistor and second and third NMOS transistors, which are serially connected between a power supply voltage and a ground voltage. Gates of the first PMOS transistor and the second NMOS transistor are connected to input data. A gate of the third NMOS transistor is connected to a clock pulse signal. A logic level of a first intermediate node between the first PMOS transistor and the second NMOS transistor is latched by a first latch. The flip-flop further includes a fourth PMOS transistor and fifth and sixth NMOS transistors, which are serially connected between a power supply voltage and a ground voltage. Gates of the fourth PMOS transistor and the fifth NMOS transistor are connected to the first intermediate node. A gate of the sixth NMOS transistor is connected to the clock pulse signal.

Abstract: A method for extending lifetime reliability of CMOS circuitry includes coupling a first switching device between a logic high supply rail/logic low supply rail, and coupling a virtual supply rail to the CMOS circuitry. In a first mode of operation the first switching device supplies the full voltage value between the logic high supply rail and the logic low supply rail, and in a second mode of operation, the first switching device isolates the virtual supply rail from the logic high supply rail/logic low supply rail, thereby reducing the voltage supplied to the CMOS circuitry. A second switching device is coupled between the virtual supply rail and the logic low supply rail/logic high supply rail, wherein in a third mode of operation, the voltage on the virtual supply rail and the logic low supply rail/logic high supply rail is equalized.