Abstract: Integrated circuits such as programmable integrated circuits may have configuration random-access memory elements. The configuration random-access memory elements may be loaded with configuration data to customize programmable circuitry on the integrated circuits. Each memory element may have a bistable element that is powered using a positive power supply voltage and a negative power supply voltage. Programmable transistors in the programmable circuitry may have gates coupled to outputs of the bistable elements. The programmable transistors may have gate insulators that are thinner than gate insulators in the transistors of the bistable elements and may have threshold voltages of about zero volts. During operation, some of the configuration random-access memory elements may supply negative voltages to their associated programmable transistors so that the programmable transistors are provided with gate-source voltages of less than zero volts.

Abstract: The exemplary embodiments provide a resilient integrated circuit. An exemplary IC comprises a plurality of composite circuit elements, a state machine element (SME), and a plurality of communication elements. Each composite circuit element comprises an element controller, an element interface and a selected circuit element which may vary by element type, and which may be configurable. The state machine element assigns various functions based on element type, such as assigning a first configuration to a first element type, assigning a second configuration to a second element type, and providing a first data link for the corresponding assignments. The element controller controls the execution of data operations by the circuit element. Function assignment, routing, fault detection, and re-assignment and data re-routing can occur in real time for a wide variety of programs and algorithms, providing for the IC to continue the same functioning despite defects which may arise during operation.

Abstract: Integrated circuits with memory elements are provided. An integrated circuit may include logic circuitry formed in a first portion having complementary metal-oxide-semiconductor (CMOS) devices and may include at least a portion of the memory elements and associated memory circuitry formed in a second portion having nano-electromechanical (NEM) relay devices. The NEM and CMOS devices may be interconnected through vias in a dielectric stack. Devices in the first and second portions may receive respective power supply voltages. In one suitable arrangement, the memory elements may include two relay switches that provide nonvolatile storage characteristics and soft error upset (SEU) immunity. In another suitable arrangement, the memory elements may include first and second cross-coupled inverting circuits. The first inverting circuit may include relay switches, whereas the second inverting circuit includes only CMOS transistors.

Abstract: The logic circuit includes at least one variable resistance device configured such that a resistance value of the at least one variable resistance device varies according to at least one selected value. The selected value is selected from among a voltage and a current of an input signal, and the at least one variable resistance device is configured to memorize the resistance value. The logic circuit is configured to store multi-level data by setting the memorized resistance value.

Abstract: Aspects of the disclosure provide a clock gate circuit for generating a clock signal. The clock gate circuit includes a multiplexer and a logic module coupled to the multiplexer. The multiplexer is configured to receive a first logic signal at a first data input, a second logic signal at a second data input, and a reference clock signal at a selector input, and to output the clock signal having a logic state selected from one of the first logic signal or the second logic signal based on transitions of the reference clock signal. The logic module includes at least one of an XNOR and an XOR module and is configured to provide an output signal that is responsive to performing at least one of an XNOR and an XOR operation of the output of the multiplexer and an enable signal that enables or disables the clock gate circuit to generate the clock signal.

Abstract: A programmable logic region on a programmable integrated circuit may include a first set of look-up tables that receive programmable logic region input signals and a second set of look-up tables that produce programmable logic region output signals. Multiplexer circuitry may be interposed between the first and second sets of look-up tables. The multiplexer circuitry may receive the programmable logic region input signals in parallel with the output signals from the first set of look-up tables and may provide corresponding selected signals to the second set of look-up tables. The programmable logic region input signals may be shared by the first and second sets of look-up tables. Logic circuitry may be coupled to outputs of the first and second sets of look-up tables. The logic circuitry may be configured to logically combine output signals from the first and second sets of look-up tables.

Abstract: A programmable analog device in which data can be held even when supply of a power supply potential is stopped. The programmable circuit includes unit cells connected in parallel or in series, and each of the unit cells includes an analog element. A conduction state of each of the unit cells is changed between an on state and an off state. Each of the unit cells includes, as a switch of the unit cell, a first transistor having a sufficiently low off-state current and a second transistor, a gate electrode of the second transistor being electrically connected to a source or drain electrode of the first transistor. The conduction state of the unit cell is controlled with a potential of the gate electrode of the second transistor, which can be kept even when no power is supplied thanks to the low off-state current of the first transistor.

Abstract: A low-power programmable LSI that can perform dynamic configuration is provided. The programmable LSI includes a plurality of logic elements. The plurality of logic elements each include a configuration memory. Each of the plurality of logic elements performs different arithmetic processing and changes an electrical connection between the logic elements, in accordance with the configuration data stored in the configuration memory. The configuration memory includes a set of a volatile storage circuit and a nonvolatile storage circuit. The nonvolatile storage circuit includes a transistor whose channel is formed in an oxide semiconductor layer and a capacitor whose one of a pair of electrodes is electrically connected to a node that is set in a floating state when the transistor is turned off.

Abstract: Some embodiments provide an integrated circuit (‘IC’). The IC includes multiple configurable circuits that configurably perform operations of a user design based on configuration data. The IC also includes a configurable trigger circuit that receives a set of configuration data that specifies an operational event. The configurable trigger circuit also determines whether the operational event has occurred during implementation of the user design of the IC. Additionally, the operational trigger event outputs a trigger signal upon determining that the operational trigger event has occurred.

Abstract: A function cell comprising a first field effect transistor (FET) device, a second FET device, a first node connected to a gate terminal of the first FET device and a gate terminal of the second FET device, wherein the first node is operative to receive a voltage signal from an alternating current (AC) voltage source, an amplifier portion connected to the first FET device and the second FET device, the amplifier portion operative to receive a signal from the first FET device and the second FET device, a phase comparator portion having a first input terminal connected to an output terminal of the amplifier and a second input terminal operative to receive the voltage signal from the AC voltage source, the phase comparator portion operative to output a voltage indicative of a bit of a binary value.

Abstract: Disclosed herein is an ASIC having a base array of function blocks. Each function block includes a plurality of primitive cells. Each primitive cell is defined by a component from a standard cell library. The base array is prefabricated for use later with a custom circuit design.

Abstract: An object of the present invention is to provide a programmable logic device which has short start-up time after supply of power is stopped, is highly integrated, and operates with low power. In a programmable logic device including an input/output block, a plurality of logic blocks each including a logic element, and a wiring connecting the plurality of logic blocks, the logic element has a configuration memory for holding configuration data and a look-up table including a selection circuit. The configuration memory includes a plurality of memory elements each of which includes a transistor whose channel region is in an oxide semiconductor film and an arithmetic circuit provided between the transistor and the selection circuit. Configuration data is selectively changed and output by the selection circuit in accordance with an input signal.

Abstract: A selectable latch has a pair of parallel pass gates (a first parallel pass gate that receives a seed signal, and a second parallel pass gate that receives a data signal). A first latch logic circuit performs logic operations using signals output by the parallel pass gates to produce an updated data signal. An additional pass gate is operatively connected to the first latch logic circuit. An additional pass gate controls passage of the updated data signal. The output of the parallel pass gates and the additional pass gate is connected to a feedback loop. The feedback loop operates as a dynamic latch for high frequency applications or as a static latch for low frequency applications. Thus, the selectable latch comprises two inputs into the pair of parallel pass gates and performs only one of four logical operations on a received data signal.

Abstract: A logic processing device, containing an application specific integrated circuit (“ASIC”) and field programmable gate array (“FPGA”), capable of automatically interfacing between ASIC and FPGA is disclosed. The logic processing device, in one aspect, includes a phase adjustment circuit, ASIC, and configurable logic circuit (“CLC”) wherein the CLC can be an FPGA. While ASIC is able to perform a specific function in accordance with an ASIC clock domain, the CLC is capable of performing a programmable logic function in accordance with an FPGA clock domain. The phase adjustment circuit is used to automatically facilitate a communication between the ASIC and the CLC in accordance with the ASIC clock domain and the FPGA clock domain.

Abstract: The exemplary embodiments provide a reconfigurable integrated circuit architecture comprising: a configurable circuit element configurable for a plurality of data operations, each data operation corresponding to a context of a plurality of contexts; a plurality of input queues; a plurality of output queues; one or more configuration and control registers to store, for each context of the plurality of contexts, a plurality of configuration bits, a run status bit, and a plurality of bits designating at least one data input queue and at least one data output queue; and an element controller coupled to the configurable circuit element and to the one or more configuration and control registers, the element controller to allow loading of a context configuration and execution of a data operation upon the arrival of input data in the context-designated data input queue when the context run status is enabled and the context-designated data output queue has a status to accept output data.

Abstract: Integrated circuits with memory elements are provided. An integrated circuit may include logic circuitry formed in a first portion having complementary metal-oxide-semiconductor (CMOS) devices and may include at least a portion of the memory elements and associated memory circuitry formed in a second portion having nano-electromechanical (NEM) relay devices. The NEM and CMOS devices may be interconnected through vias in a dielectric stack. Devices in the first and second portions may receive respective power supply voltages. In one suitable arrangement, the memory elements may include two relay switches that provide nonvolatile storage characteristics and soft error upset (SEU) immunity. In another suitable arrangement, the memory elements may include first and second cross-coupled inverting circuits. The first inverting circuit may include relay switches, whereas the second inverting circuit includes only CMOS transistors.

Abstract: Various techniques are provided to flexibly update data fields stored in multi-bit registers. In one example, a method of updating a control register within an integrated circuit includes storing a plurality of initial bit values in the control register within the integrated circuit. The method also includes receiving a data set comprising one or more corrective bit values and one or more non-corrective bit values. The method also includes performing a logic operation on the received data set and the initial bit values to provide updated bit values. The method also includes replacing the initial bit values with the updated bit values in the control register.

Abstract: A sequential voltage output circuit is connected between a power supply and a number of loads. The voltage sequence output circuit includes a complex programmable logic device (CPLD) and a number of switching circuits. When the CPLD receives a power on signal, the CPLD outputs a number of control signals sequentially through a number of outputs. When a switching circuit receives a control signal from the CPLD, the switching circuit allows the power supply to supply power to a corresponding load.

Abstract: A first and second plurality of gates are coupled respectively between first and second source storage elements and first and second destination storage elements. The first and second plurality of gates are slept to reduce leakage current in the plurality of gates under certain conditions by turning off respective one or more transistors between the first and second plurality of gates and power supplies. A third plurality of gates are maintained in a reduced leakage current state (sleep state) or regular state (wake state) based on conditions associated with the source and destination elements for the first and second plurality of gates.

Abstract: Sequential electronic circuit (10) reacting on a rising edge and a falling edge of a clock signal (CK), comprising a first (1) and a second (2) D-type flip-flop, a main multiplexer (3) coupled at input to the flip-flops (1 and 2), the circuit (10) comprising a first input receiving the clock signal (CK) and a second input receiving a control signal (TE) so as to control the circuit (10) according to a normal operating mode and a test operating mode making it possible to check the proper operation of the sequential electronic circuit (10). The clock signal (CK) used in the normal operating mode is used to gate the circuit (10) during the test operating mode.

Abstract: A technique for manufacturing a three-dimensional integrated circuit includes stacking a memory unit on a first die that includes a first computational unit. In this case, the memory unit is included in a second die. A second computational unit that is included in a third die is stacked on the second die. Sets of vertical vias that extend through the first, second, and third dies are connected to connect components of the first and second computational units and the memory unit. Multiplexers of the first and second computational units are configured to selectively couple the components to different ones of the sets of vertical vias responsive to respective control words for each of the first and third dies.

Abstract: Programmable logic units are described. A described unit includes one or more first logic elements that are individually programmable to be one of a plurality of first functions; one or more second logic elements that are a decoder; one or more third logic elements that are individually programmable to be one of a plurality of second functions; and a programmable interconnect array that selectively forms one or more interconnections within a group including the logic elements, one or more input interfaces, and one or more output interfaces. The array is programmable in routing one or more input signals to at least a portion of the logic elements, routing one or more intermediate signals among at least a portion of the logic elements, and routing one or signals from at least a portion of the logic elements to produce one or more output signals via the output interface.

Abstract: Aspects of the invention provide for improving a success rate of an engineering design change (ECO) for an integrated circuit. In one embodiment, aspects of the invention include a method for improving a success rate of an engineering design change (ECO) for an integrated circuit, including: identifying a plurality of spare latches within the integrated circuit; determining an input driver for each of the spare latches; and replacing each input driver with a programmable gate array, such that the programmable gate array is programmed to a functionality of the input driver.

Abstract: The exemplary embodiments provide a reconfigurable integrated circuit capable of on-chip configuration and reconfiguration, comprising: a plurality of configurable composite circuit elements; a configuration and control bus; a memory; and a sequential processor. Each composite circuit element comprises: a configurable circuit; and an element interface and control circuit, the element interface and control circuit comprising an element controller and at least one configuration and control register to store one or more configuration and control words. The configuration and control bus is coupled to the plurality of configurable composite circuit elements, and comprises a plurality of address and control lines and a plurality of data lines. The sequential processor can write configurations to the configuration and control registers of an addressed configurable composite circuit element to configure or reconfigure the configurable circuit.

Abstract: In one embodiment, a programmable logic device includes configuration memory, an SPI port for receiving a bitstream, a chip select output pin, and configuration control circuitry. The chip select output pin can provide a chip select signal having a first logic state for selecting another device (such as another PLD) to receive a bitstream and a second logic state for de-selecting the other device. The configuration control circuitry is responsive to a command embedded in the received bitstream to drive the chip select output pin from the second logic state to the first logic state, thereby selecting the other device to receive the bitstream. Several such PLDs connected in a daisy chain can thus be configured from a single configuration source or have their configuration data read back while so connected.

Abstract: A skewed placement grid for an integrated circuit (IC) is disclosed. In one embodiment, an IC includes a placement grid which includes a plurality of cells. Each of the plurality of cells includes one of a corresponding plurality of circuits. A center point of each of the cells is located at a unique coordinate along a first axis and a second axis with respect to each of the other ones of the plurality of cells. The IC further includes a first plurality of signal interconnections, wherein each of the plurality of signal interconnections is coupled to a corresponding one of the first plurality of circuits.

Abstract: A field programmable gate array is disclosed, which comprises at least one logic element having at least one switching element. The switching element comprises a static support element and a movable connecting element for providing a non-volatile electrical connection.

Abstract: Some embodiments of the invention provide an integrated circuit (IC) with configurable input/output (I/O) circuits for optimally operating with two or more interfaces. Some embodiments optimally operate over the two or more interfaces by supporting a particular voltage for each interface. Also, some embodiments optimally operate over two or more interfaces by supporting a particular frequency for each supported voltage whereby supporting a particular frequency involves producing sufficient current drive at each voltage to support the particular frequency.

Abstract: An object of the present invention is to provide a technique of reducing the leakage current of a drive circuit for driving a circuit that must retain a potential (or information) when in its standby state. A semiconductor integrated circuit device of the present invention includes a drive circuit for driving a circuit block. This drive circuit is made up of a double gate transistor with gates having different gate oxide film thicknesses. When the circuit block is in its standby state, the gate of the double gate transistor having a thinner gate oxide film is turned off and that having a thicker gate oxide film is turned on. This arrangement allows a reduction in the leakage currents of both the circuit block and the drive circuit while allowing the drive circuit to deliver or cut off power to the circuit block.

Abstract: A computer device which performs logic synthesis using hardware description and a component in a cell library and generates a net list of a logic circuit including a series path of a clock synchronous sequential circuit and a combinational circuit performs optimization processing for decreasing the number of gate stages in a critical path between sequential circuits in the data path by using a third sequential circuit having a negative-logic input terminal and a negative-logic non-inverted output terminal and a fourth sequential circuit having a negative-logic input terminal and a negative-logic inverted output terminal in addition to a first sequential circuit having a positive-logic input terminal and a positive-logic non-inverted output terminal and a second sequential circuit having a positive-logic input terminal and a positive-logic inverted output terminal.

Abstract: Methods, circuits, and systems for preventing data remanence in memory systems are provided. Original data is stored in a first memory, which may be a static random access memory (SRAM). Data is additionally stored in a second memory. Data in the first memory is periodically inverted, preventing data remanence in the first memory. The data in the second memory is periodically inverted concurrently with the data in the first memory. The data in the second memory is used to keep track of the inversion state of the data in the first memory. The original data in the first memory can be reconstructed performing a logical exclusive-OR operation between the data in the first memory and the data in the second memory.

Abstract: A low-power programmable LSI that can perform dynamic configuration is provided. The programmable LSI includes a plurality of logic elements. The plurality of logic elements each include a configuration memory. Each of the plurality of logic elements performs different arithmetic processing and changes an electrical connection between the logic elements, in accordance with the configuration data stored in the configuration memory. The configuration memory includes a set of a volatile storage circuit and a nonvolatile storage circuit. The nonvolatile storage circuit includes a transistor whose channel is formed in an oxide semiconductor layer and a capacitor whose one of a pair of electrodes is electrically connected to a node that is set in a floating state when the transistor is turned off.

Abstract: An enhanced performance field programmable gate array integrated circuit comprises a field programmable gate array and other functional circuitry such as a mask-programmable gate array in the same integrated circuit. A circuit interface provides communication between the field programmable gate array, the mask-programmable gate array and the integrated circuit I/O.

Abstract: Systems, circuits and methods for software programmable logic using Spin Transfer Torque Magnetoresistive Random Access Memory (STT-MRAM) technology are disclosed. Magnetic tunnel junction (MTJ) storage elements can be formed into input planes and output planes. The input planes and output planes can be coupled together to form complex arrays that allow for the realization of logic functions.

Abstract: A semiconductor device includes a first transistor layer and a second transistor layer overlaying the first transistor layer, wherein said first transistor layer comprises a plurality of flip-flops each having a selectively coupleable additional input generated by said second transistor layer.

Abstract: Systems and methods for managing a write operation are described. The systems include a logic element (LE) including an N-input look-up table (LUT) having a configurable random access memory (CRAM) including 2N memory cells. The systems further include a write address decoder coupled to the LE and a write address hard logic register that stores an address of one of the memory cells. N is an integer. The hard logic register removes a dependency of a timing relationship between a write address launch and a write to the CRAM on a design of an integrated circuit.

Abstract: In one embodiment, a method for restricting use of an integrated circuit (IC) is provided. A write-once memory of a programmable IC contains a first die-specific performance grade indicator. In response to receiving an input code having a second die-specific performance grade indicator with a value indicating a level of performance greater than or equal to a level of performance indicated by the first die-specific performance grade indicator, enabling operation of the IC. In response to receiving a configuration bitstream having the second die-specific performance grade indicator with a value indicating a level of performance less than a level of performance indicated by the first die-specific performance grade indicator, preventing operation of the IC.

Abstract: A logic device implementing configurations for ROM based logic uses arrays of memory cells to provide outputs based on inputs received at the logic device. The logic device stores values in the memory cells that are accessed when an input is received. The memory cells are transistors that provide values of ‘1’ or ‘0.’ Various configurations reduce the number of transistors while implementing the memory block by utilizing a single bitline or a dynamic precharge implementation.

Abstract: The exemplary embodiments provide a resilient integrated circuit. An exemplary IC comprises a plurality of composite circuit elements, a state machine element (SME), and a plurality of communication elements. Each composite circuit element comprises an element controller, an element interface and a selected circuit element which may vary by element type, and which may be configurable. The state machine element assigns various functions based on element type, such as assigning a first configuration to a first element type, assigning a second configuration to a second element type, and providing a first data link for the corresponding assignments. The element controller controls the execution of data operations by the circuit element. Function assignment, routing, fault detection, and re-assignment and data re-routing can occur in real time for a wide variety of programs and algorithms, providing for the IC to continue the same functioning despite defects which may arise during operation.

Abstract: Some embodiments of the invention provide a configurable integrated circuit (“IC”). The configurable IC includes a set of configurable logic circuits for configurably performing a set of functions. The configurable IC also includes a set of configurable routing circuits for routing signals to and from the configurable circuits. During several operational cycles of the configurable IC, a set of data registers are defined by the configurable routing circuits. These data registers may be used wherever a flip-flop can be used.

Abstract: The logic cells (HLEs) of a structured application-specific integrated circuit (structured ASIC) can be used to provide memory blocks of various sizes. Any one or more of several techniques may be employed to facilitate doing this for various user designs that may have different requirements (e.g., in terms of size) for such memory blocks. For example, pre-designed macros of memory blocks may be provided and then combined as needed to provide memory blocks of various sizes. Placement constraints may be observed for certain portions of the memory circuitry (e.g., the memory core), while other portions (e.g., address predecoder circuitry, write and read data registers, etc.) may be located relatively freely.

Abstract: A quadrature output high-frequency RF divide-by-two circuit includes a pair of differential complementary logic latches. The latches are interconnected to form a toggle flip-flop. Each latch includes a tracking cell and a locking cell. In a first embodiment, the locking cell includes two complementary logic inverters and two transmission gates. When the locking cell is locked, the two gates are enabled such that the locked (i.e., latched) signal passes through both transmission gates and both inverters. In one advantageous aspect, the tracking cell only involves two transmission gates. Due to the circuit topology, the first embodiment is operable from a low supply voltage at a high operating frequency while consuming a low amount of supply current. In a second and third embodiment, the tracking cell involves a pair of inverters. The sources of the transistors of the inverters are, however, coupled together thereby resulting in performance advantages over conventional circuits.

Abstract: Some embodiments provide a circuit for accessing stored data in a configurable IC that includes several configurable circuits. The IC also includes several storage circuits. Each storage circuit has (1) several storage elements for storing data for the configurable circuits, and (2) output circuitry for outputting data stored in the storage elements. The output circuitry includes a first set of interconnects for receiving at least a first repeating periodic signal and for periodically outputting data from at least two storage elements to the configurable circuits.

Abstract: A programmable integrated circuit having a plurality of individually controlled voltage domains. Each voltage domain includes logic circuitry powered by a respective power network. The voltage magnitude of each power network is independently selectable. Each of a plurality of level shifters couples a first and second one of the voltage domains, couples a first port of the logic circuitry of the first voltage domain to a second port of the logic circuitry of the second voltage domain, and shifts from a first signaling protocol of the first port to a second signaling protocol of the second port. The first signaling protocol is referenced to the voltage magnitude of the first voltage domain, and the second signaling protocol is referenced to the voltage magnitude of the second voltage domain. Means are disclosed for controlling the voltage magnitude of the respective power network of one or more of the voltage domains.

Abstract: A programmable logic device includes a plurality of repeating units, each of which includes interconnecting lines, a logic block comprising logic circuits, and a configuration memory block including a plurality of configuration memory circuits. One of the plurality of repeating units includes: a selection device coupled to output data of the plurality of configuration memory circuits and a shift chain segment input; and a flip flop receiving output of the selection device to output a shift chain segment output.

Abstract: A semiconductor integrated circuit judges whether a power unit is performing a discharge operation or a charge operation. To reduce clock skew between a plurality of logic blocks in the semiconductor integrated circuit, when the power unit is performing the charge operation, the semiconductor integrated circuit determines a logic block that needs to be operated for the execution of a target process, as an operation block whose operation is to be started, and, determines, in the rest of the logic blocks, a logic block having a termination rate whose value is larger than a value of the minimum termination rate, as the operation block whose operation is to be started, the value of the termination rate being larger by more than a predetermined value.

Abstract: An apparatus for driving a display device includes a plurality of stage connected to each other, wherein each stage includes first to seventh transistors and first and second capacitors, the seventh transistor is connected to one terminal of the first capacitor, and a ratio of an area of the first capacitor to a channel width of the seventh transistor is less than 40. Accordingly, since the ratio of the area of the capacitor to the channel width of the transistor is less than 40, deterioration may be remarkably reduced in a low temperature test.

Abstract: Two latches store the state of a data signal at a transition of a clock signal. Comparison logic compares the outputs of the two latches and produces a signal to indicate whether the outputs are equal or unequal. Systems using the latches and comparison logic are described and claimed.

Abstract: A programmable integrated circuit (IC) with mirrored interconnect structure. The IC includes a plurality of arrangements, which are horizontally arranged. Each arrangement includes a first logic column, an interconnect column, and a second logic column. Each interconnect column includes programmable interconnect blocks (148), and each of the first and second logic columns includes programmable logic blocks. Each programmable interconnect block provides a plurality of first input and output ports on a first side and a plurality of second input and output ports on a second side. The first ports and the first side of each of the programmable interconnect blocks physically mirror the second ports and the second side of the programmable interconnect block. The ports of the programmable interconnect blocks are coupled to the ports of the programmable logic blocks in the first and second logic columns.

Abstract: Configurable time-borrowing flip-flops may be based on configurable pulse generation circuitry and pulse latches. The circuitry may use a self-timed architecture that controls the width of clock pulses that are generated so that the pulse latches that are controlled by the clock pulses exhibit a reduced risk of race through conditions. Latch circuitry may be provided that is based on a pulse latch and an additional latch connected in series with the pulse latch. In situations in which there is a potential for race through conditions on an integrated circuit, the additional latch may be switched into use to convert the latch circuitry into an edge-triggered flip flop. Clock trees may be provide with configurable shorting structures that help to reduce clock skew. Low-contention clock drivers may drive signals onto the clock tree paths.