Abstract: Performance monitors are placed on computational units in different clock domains of an integrated circuit. A central dispatcher generates trigger signals to the performance monitors to cause the performance monitors to respond to the trigger signals with packets reporting local performance counts for the associated computational units. The data in the packets are correlated into a single clock domain. By applying a trigger and reporting system, the disclosed approach can synchronize the performance metrics of the various computational units in the different clock domains without having to route a complex global clock reference signal to all of the performance monitors.

Abstract: A single pole double throw (SPDT) switch is fabricated on an integrated circuit (IC) and may comprise two radio frequency (RF) switching devices each having a separate DC blocking capacitor coupled between respective RF switching devices and a common node. A DC connection is provided between the two RF switching devices with a thin electrically conductive line. This thin electrically conductive line provides for increased isolation between the two RF switching devices and decreased insertion loss. The increased isolation and/or decreased insertion loss is accomplished by tuning the thin electrically conductive line through the characteristic impedance of the line when impedance matching conditions are met. Undesired circuit resonance(s) in the SPDT switch may be substantially reduced by using two or more thin electrically conductive lines that further reduce the thin electrically line(s) inductance.

Abstract: Temperature-independent delay elements and oscillators are disclosed. In one design, an apparatus includes at least one delay element, a bias circuit, and a current source. The delay element(s) receive a charging current from the current source and provide a delay that is dependent on the charging current. Each delay element may be a current-starved delay element. The delay element(s) may be coupled in series to implement a delay line or in a loop to implement an oscillator. The bias circuit controls generation of the charging current based on a function of at least one parameter (e.g., a switching threshold voltage) of the at least one delay element in order to reduce variations in delay with temperature. The current source provides the charging current for the delay element(s) and is controlled by the bias circuit.

Abstract: A sample-and-hold circuit for generating a variable sample delay time of a transformer includes a discharge detection unit, a sample delay time generation unit, and a comparator. The discharge detection unit generates a first voltage according to a first turning-on signal and a first reference current. Length of the first turning-on signal is varied with a discharge time of a present period of the transformer. The sample delay time generation unit generates a second voltage according to the first turning-on signal and a second reference current. The comparator generates a sample signal to a control circuit of the transformer according to a first voltage corresponding to a previous period of the transformer and a second voltage corresponding to the present period of the transformer. The first reference current is K times the second reference current, and 0<K<1.

Abstract: Programmable delay circuitry, which includes an input buffer circuit and variable delay circuitry, is disclosed. The variable delay circuitry includes an input stage, a correction start voltage circuit, and a variable delay capacitor. The input buffer circuit is coupled to the input stage, the correction start voltage circuit is coupled to the input stage, and the variable delay capacitor is coupled to the input stage. The programmable delay circuitry is configured to provide a fixed time delay and a variable time delay.

Abstract: Delay circuits are described for which the delay remains substantially constant within a desired range of variation of supply voltage and/or temperature.

Abstract: To cancel a delay time that occurs in a delay circuit due to temperature and voltage changes. The delay circuit includes a plurality of first and second inverters that are each composed of an N-channel first transistor and a P-channel second transistor connected in series, and P-channel third transistors that are connected between a first power supply wiring and the input nodes of the second inverters. According to the present invention, the presence of the third transistors cancels characteristic variations of the second transistors included in the respective plurality of inverters even if there are changes in temperature, voltage, etc. Consequently, when temperature, voltage, or the like changes, variations in the amount of delay of the entire delay circuit can be regarded as resulting from characteristic variations of the first transistors.

Abstract: A zero bias power detector comprising a zero bias diode and an output boost circuit is provided. The output boost circuit comprises a zero bias transistor. The zero bias diode is not biased but outputs a rectifying signal according to a wireless signal. The zero bias transistor, not biased but coupled to the zero bias diode, is used for enhancing the rectifying signal.

Abstract: An apparatus for controlling clock skew in an integrated circuit (IC) includes timing circuitry operative to generate a clock signal for distribution in the IC and at least one buffer circuit operative to receive the clock signal, or a signal indicative of the clock signal, and to generate a delayed version of the clock signal as an output thereof. The buffer circuit includes at least first and second inverter stages and a resistive-capacitive (RC) loading structure. An output of the first inverter stage is connected to an input of the second inverter stage via the RC loading structure. The buffer circuit has a delay associated therewith that is selectively varied as a function of one or more adjustable characteristics of the RC loading structure. Clock skew in the IC is controlled as a function of the delay of the buffer circuit.

Abstract: A calibration circuit and a calibration method are provided. The calibration circuit has a delay circuit, a phase detector, and a controller. The delay circuit delays an input signal to output an output signal, wherein a delay time between the input signal and the output signal is related to an equivalent capacitance and an equivalent resistance of the delay circuit. The phase detector coupled to the delay circuit compares the phases of the input signal and the output signal. The controller coupled to the delay circuit and the phase detector generates a control signal according to the comparison result of the phase detector to adjust the equivalent resistance of the delay circuit.

Abstract: An apparatus for controlling clock skew in an integrated circuit (IC) includes timing circuitry operative to generate a clock signal for distribution in the IC and at least one buffer circuit operative to receive the clock signal, or a signal indicative of the clock signal, and to generate a delayed version of the clock signal as an output thereof. The buffer circuit includes at least first and second inverter stages and a resistive-capacitive (RC) loading structure. An output of the first inverter stage is connected to an input of the second inverter stage via the RC loading structure. The buffer circuit has a delay associated therewith that is selectively varied as a function of one or more adjustable characteristics of the RC loading structure. Clock skew in the IC is controlled as a function of the delay of the buffer circuit.

Abstract: The semiconductor apparatus includes a reference delay value check unit configured to receive a source signal and delay the source signal to generate a reference delay signal; a process delay value check unit configured to receive the source signal and delay the source signal to generate a process delay signal; and a signal generation unit configured to receive the reference delay signal and the process delay signal, receive an input signal, and variably delay the input signal based on the reference delay signal and the process delay signal to generate an output signal.

Abstract: A programmable delay element with a variable delay generator employs feed forward and feedback control signals to corresponding feed forward and feedback control elements integrated within the variable delay generator. The variable delay generator is responsive to a control signal. The variable delay generator uses transfer switches to couple reactive circuit elements to a signal node in accordance with the control signal. The feed forward element couples a fixed voltage to corresponding nodes of the feed back element. The feedback element completes a bypass circuit to apply the fixed voltage to the signal node once the programmable delay element has delayed a source signal. The feed forward element is responsive to a buffered version of the source signal. The feedback element is responsive to a buffered version of the output of the delay element. A corresponding method for reducing frequency induced delay variation in a programmable delay element is disclosed.

Abstract: A fine delay adjustment device is disclosed. The fine delay adjustment device in accordance with the present invention has at least one delay buffer having an output impedance; a capacitor connected to the delay buffer in series; and a variable resistive unit connected with the capacitor in series. The variable resistive unit has a variable resistance of the same order as the output impedance of the delay buffer. The fine delay adjustment of the present invention is capable of providing sub-ps adjustment steps. In the mean while, an increment due to the fine delay adjustment added to delay time is limited.

Abstract: A time-delay buffer having a CMOS inverter and a capacitor is disclosed. The CMOS inverter of the time-delay buffer has a silicide layer partially disposed on the transistor gate of the CMOS and a non-silicide region lain in between the silicide layers. Therefore, the time-delay buffer of the present invention has a resistance therein, and results in a period of time delayed in the circuit.

Abstract: A stage by stage delay current-summing slew rate controller includes a delay controller, a delay cell array, a current source array, a switch array, a load. The delay cell array includes N delay cells, the switch array includes N switches, and the switch includes N current sources, wherein N>1. The delay controller is connected with the control ports of the delay cells respectively, and the delay cells are connected with the control terminal of the switches respectively. One of the connecting terminals of the switch is connected with the output end of the current source, and the other end of the connecting terminals of the switch is connected with one end of the load, and the other end of the load is connected to the ground.

Abstract: A delay circuit is used for receiving an input signal from a signal source. The delay circuit includes a delay unit, a switch unit, and a generator. The switch unit is used for receiving a voltage from a power supply and selectively transmitting the voltage to the delay unit according to the input signal. The generator is coupled to the power supply for generating an output signal. The output signal is equivalent to the input signal that is delayed for a predetermined time period. Wherein the delay unit is used for generating an electrical signal according to the voltage and transmitting the electrical signal to the generator. The delay unit includes an adjustable capacitor coupled between ground and an interconnection of the switch unit and the generator. An electronic device including the delay circuit is also provided.

Abstract: A serial interface interacting with a transmission pad system circuitry wherein a differential impedance is reckoned across the system voltage source, includes a scheme for controlling transmitter rise-fall transitions (to selectively speed up or slow down transitions) without requiring additional timing controls or affecting reflection coefficient of the transmitter port. The scheme uses at least one pre-charged capacitor, e.g., PMOS capacitor, interacting with the transmitter pad and connected through resistances or otherwise across the differential impedance with a switch. A modified scheme uses first and second parallely connected PMOS capacitors connectable with the transmission pad by switches, which may be NMOS switches. The scheme may be used in a MIPI D-PHY compliant DSI transmitter operating at, for e.g. 800 Mbps, and low signal common-modes. The scheme controls signal transition times of high speed circuitry including transmitters and uses a DATA signal which is already available to the circuitry.

Abstract: Delay circuits are provided. Some embodiments of delay circuits herein include a delay line including multiple delay cells connected in series and a variable voltage supplier operative to output a voltage value proportional and/or inversely proportional to a temperature. Delay circuits may include at least one loading capacitor that includes a first end that is connected to an output port of the delay cell and a second end that is connected to an output port of the variable voltage supplier, the at least one loading capacitor including a capacitance that is decreased corresponding to an increase in temperature when a positive voltage is applied across the first end and the second end of the at least one loading capacitor.

Abstract: A converter includes a time-delay circuit for a PWM signal, applied to input of the time-delay circuit, by which rising edges of the PWM signal are delayed by an ON delay and falling edges of the PWM signal are delayed by an OFF delay, in order to form a drive signal, available at the output of the time-delay circuit, for a semiconductor switch element. The time-delay circuit includes two resistors, two capacitors, a diode and a comparator, and is therefore particularly easy to implement.

Abstract: The present invention relates to a parameterization method for a converter (1, 2) of the speed controller type, the said converter (1, 2) being connected to an electrical load (3) by means of an electrical cable (4) comprising at least two conductors, the method consisting in: generating common-mode current on the electrical cable (4) starting from a pulsed voltage comprising a first voltage edge (11, 13) and a second voltage edge (12, 14) delayed by a delay time (T) with respect to the first voltage edge (11, 13), measuring the common-mode current generated, making the delay time (T) between the two voltage edges (11, 12, 13, 14) generated vary, and determining an optimal delay time (T2) starting from a quantity (Ipeak, Ieff) representative of the common-mode current measured for the various values of the delay time (T).

Abstract: Delay line circuits include a plurality of delay cells connected in series. The delay cells respectively include a first to a third logic gate. The first logic gate, in response to a selection signal, generates a first signal based on an input signal. The second logic gate generates a second signal based on the input signal in response to the selection signal. The third logic gate generates a third signal based on either a return signal or an output signal of the second logic gate.

Abstract: A clock and data recovery system using a distributed variable delay line is provided. The clock and data recovery system can use a delay-locked loop methodology to align a local clock with an incoming data stream. The variable delay line can include a transmission line coupled with a plurality of variable capacitors responsive to a control voltage. The variable delay line can also have a ladder configuration of multiple LC subcircuits each having a variable impedance responsive to a control voltage.

Abstract: The invention discloses a delay-locked loop circuit with input means for a signal that is to be delayed, the input means comprising means for splitting the input signal into a first and a second branch. The signal in the first branch is connected to a component for delaying the signal, and the signal in the second branch is used as a non-delayed reference for the delay caused by the delay component in the first branch. The delay component is a passive tunable delay line, and the circuit comprises tuning means for the tunable delay line, the tuning means being affected by said reference signal, and the first branch comprises output means for outputting a delayed signal with a chosen phase delay. Suitably, the delay component is continuously tunable, for example a tunable ferroelectric delay line.

Abstract: A DLL-based programmable clock generator using a threshold-trigger delay element and an edge combiner is proposed. A threshold-trigger delay element with full swing complementary output signals consumes no dc power. It exhibits small delay error resulting reduced out jitter. It also increases the linearity of delay time versus control voltage. The circular edge combiner can multiply the input signal at a lower supply voltage. The rise and fall time of output signal are more symmetrical. It also present the multiplication factor of the clock generator can be easy to choose with the increasing of the number of delay elements.

Abstract: The present invention relates to a parameterization method for a converter (1, 2) of the speed controller type, the said converter (1, 2) being connected to an electrical load (3) by means of an electrical cable (4) comprising at least two conductors, the method consisting in: generating common-mode current on the electrical cable (4) starting from a pulsed voltage comprising a first voltage edge (11, 13) and a second voltage edge (12, 14) delayed by a delay time (T) with respect to the first voltage edge (11, 13), measuring the common-mode current generated, making the delay time (T) between the two voltage edges (11, 12, 13, 14) generated vary, and determining an optimal delay time (T2) starting from a quantity (Ipeak, Ieff) representative of the common-mode current measured for the various values of the delay time (T).

Abstract: A device is provided for transmitting electromagnetic signals between at least one first and at least one second functional unit, especially in the high frequency range. The device includes an electrically insulating substrate with a top and a bottom, a first electrically conductive layer of a first coating material on the bottom of the substrate, which layer can be connected to a reference voltage, and a second electrically conductive layer of a second coating material on the top of the substrate. The second electrically conductive layer can be, in at least one region, of fields of the second coating material that are spatially separated from one another and electrically insulated with respect to one another.

Abstract: A clock and data recovery system using a distributed variable delay line is provided. The clock and data recovery system can use a delay-locked loop methodology to align a local clock with an incoming data stream. The variable delay line can include a transmission line coupled with a plurality of variable capacitors responsive to a control voltage. The variable delay line can also have a ladder configuration of multiple LC subcircuits each having a variable impedance responsive to a control voltage.

Abstract: A voltage controlled oscillator (VCO) for use in a personal area network synthesizer includes a delay cell (100), a first current amplifier (201, 203) for amplifying an input current, a resister capacitor (RC) tuning network (207, 209, 211) for varying the amount of amplification and delay of an output of the first current amplifier. A second current amplifier (213, 215) is then used for amplifying an output current from the RC tuning network. The invention includes a unique composite voltage variable capacitor (CVVC) (300) for precisely tuning the amount of delay presented by the delay cell. The unique topology of the delay cell (100) allows it to be readily used in voltage controlled oscillators (VCOs) operable at frequencies above 1 GHz.

Abstract: An improved method and design for adjusting clock skew in a wire trace is disclosed. Aspects of the invention include a corrugated pattern wire trace bracketed by a pair of parallel conducting wire frames with wire extensions projecting between the corrugations of the wire trace. The wire frames are connected to a voltage supply. The transmission properties of the wire trace, and thus the degree of clock skew associated with the wire trace, are affected by the number of wire extensions protruding between the corrugations, their degree of penetration, as well as other factors inherent in the design. The present design can achieve the same degree of clock skew with a smaller surface area covered and with fewer resistive losses than with prior art designs.

Abstract: A delay locked loop having an adjustable capacitance stage is provided. The adjustable capacitance stage facilitates a selective post-silicon adjustment of capacitance amounts between a DLL loop filter capacitance and a power supply noise filter capacitance, thereby allowing a designer to reduce capacitance area space wastage and to obtain an optimal DLL performance level.

Abstract: In the case where the amplitude of the input signal is large, the duty ratio of the signal output from the last stage is greatly changed as compared with the input signal. In the present invention, in order to solve this problem, there is provided a cascade connection type inverter circuit in which the inverters at the odd-number stage is fed back to the input circuit of the inverter at the first stage via an impedance element, the circuit being characterized in that a switching means is connected for supplying to an input circuit of the inverter at the first stage a compensation current for compensating a disparity between the logical threshold value of the inverter at the first stage and the central voltage of the input signal when the voltage generated between the output terminal of the inverter at the first stage and the input terminal thereof exceeds a predetermined threshold value level.

Abstract: The present invention relates to an integrated circuit device and method of adjusting capacitance of a node of an integrated circuit In one embodiment, the device comprises a first digital input, a first parasitic capacitance block, a first output, a second digital input, a second parasitic capacitance block and a second output. The first parasitic capacitance block includes an inverter, a variable capacitance element, and a wire capacitance element. The first parasitic capacitance block has a capacitance that is a function of the first digital input. The first output is responsive to the first parasitic capacitance block, and the second output is responsive to the second parasitic capacitance block.

Abstract: The present invention relates to an integrated circuit device and method of adjusting capacitance of a node of an integrated circuit In one embodiment, the device comprises a first digital input, a first parasitic capacitance block, a first output, a second digital input, a second parasitic capacitance block and a second output. The first parasitic capacitance block includes an inverter, a variable capacitance element, and a wire capacitance element. The first parasitic capacitance block has a capacitance that is a function of the first digital input. The first output is responsive to the first parasitic capacitance block, and the second output is responsive to the second parasitic capacitance block.

Abstract: A ladder type clock network for reducing the skew of clock signals is provided. The clock network includes a buffer for buffering a clock signal, first delay units for delaying the output of the first buffer by a set time, second buffers connected to respective outputs of the first delay units, and second delay units connected to respective outputs of the second buffers. The first delay units and the second delay units consist essentially of the resistance and capacitance of lines through which the clock signal propagates. Accordingly, the skew of the internal clock signals is reduced, and internal clock signals having a stable duty with respect to variations in a semiconductor device manufacturing process, temperature, and power supply voltage, are generated.

Abstract: In order to provide a more flexible adjustment of signal delay times in a circuit configuration containing a line device and a number of electronic components accessing it, it is proposed to add additional capacitances, which can be varied in a controllable manner. In addition, the capacitances are to formed in a region of the existing components.

Abstract: A delay circuit includes a capacitor, a charging/discharging control circuit receptive of an input signal for controlling at least one of the charging and the discharging of the capacitor to set a delay time in accordance with a capacitance value of the capacitor, and a comparing circuit for comparing a voltage at a first terminal of the capacitor with a first reference voltage to produce an output signal which becomes inverted after the delay time when the voltage at the first terminal of the capacitor crosses over the first reference voltage during one of charging and discharging of the capacitor, and comparing a voltage at the first terminal of the capacitor with a second reference and producing an output signal which becomes inverted when the voltage at the first terminal of the capacitor is higher than the second reference voltage so that the delay time is reduced when the first terminal of the capacitor becomes short-circuited to an abnormally high voltage level.

Abstract: A universal clock generator circuit, in accordance with the present invention, includes an oscillator unit including circuitry for providing a first clock frequency. A plurality of load blocks are included. The load blocks are selectively connectable to the oscillator such that a range of clock rates are derived from the first clock frequency by selectively connecting a number of the load blocks to the oscillator unit to provide one of a plurality of clock frequencies from a same output.

Abstract: A delay circuit does not lead to excessive increase in the delay time even if the source voltage drops, and enables to control the delay time from increasing. The delay circuit is designed to delay a logic signal SIN having two logic levels consisting of a low level and a high level, such that the delay times are different for the high and low levels, and the circuit chooses either the low level or the high level and targets a logic level having a shorter delay time. That is, n-MOS transistors N11, N12 and p-MOS transistors P11, P12 are provided as MOS capacitors, so as to change from the off-state to the on-state during the transition period of a signal that appears on each node disposed on a delay path of logic signals. Such a circuit design enables to control source-voltage dependence of delay time so that, even if the source voltage drops, delay times are not increased excessively.

Abstract: A semiconductor integrated circuit device includes a plurality of data input/output terminals to transmit send/receive a plurality of input/output data signals to/from an external source, a mode set circuit to set an operation mode of the semiconductor integrated circuit device and generating a plurality of capacitance set signals according to a combination of externally applied control signals, and a plurality of variable capacitance circuits respectively provided between a predetermined reference potential and a plurality of data input/output terminals, capable of changing independently the capacitance according to a capacitance set signal.

Abstract: A voltage regulation device is for a reference cell of a dynamic random access memory arranged in lines and columns and including a plurality of memory cells. The device includes at least one capacitor of a predetermined capacitance which can be discharged during memory access.

Abstract: A RC delay time stabilizing circuit of the present invention includes an inverter which inverts a periodic input signal, a RC delay unit which is charged/discharged in accordance with an output from the inverter, a pull-up MOS transistor connected between a source voltage terminal and an output terminal of the RC delay unit and having a gate for receiving the input signal, and an output unit which generates an output signal having an identical delay time in accordance with output levels of the inverter and the RC delay unit. Such RC delay time stabilizing circuit of the present invention decreases the charging time of the RC delay unit when a periodic signal is inputted, thus being able to maintain the same delay time in each cycle of the input signal.

Abstract: A gate driving circuit for power semiconductor switch including a DC voltage source whose positive output terminal is connected to a cathode of a power semiconductor switch, a series circuit of a reactor and a turn-on switching element connected across the positive output terminal of the DC voltage source and a gate of the power semiconductor switch, a turn-off switching element connected across the gate of the power semiconductor switch and a negative output terminal of the DC voltage source, a freewheel diode connected across the negative output terminal of the DC voltage source and a junction point between the turn-on switching element and the reactor, and a control circuit for controlling the turn-on and turn-off switching elements such that the power semiconductor switch is kept non-conductive by making the first and second switching elements in off-state and in on-state, respectively, upon turning-on the power semiconductor switch, after storing energy in said reactor by changing the first switching e

Abstract: A variable loading circuit for controlling signal transmission on a signal line in an integrated circuit includes a capacitor. A loading control circuit is responsive to a control signal to variably couple the signal line and a signal node through the capacitor and thereby vary signal transmission time on the signal line. In embodiments of the present invention, the loading control circuit includes a series combination of a fuse and one or more switches. The one or more switches are responsive to respective control signals to variably couple the signal line to the signal node through the fuse and the capacitor. The variable loading circuits can be used to reduce skew among signals in systems where signal timing is critical. Related methods are also described.

Abstract: Programmable analog delay line devices for analog signal processing are constructed on a single integrated circuit chip using a switched capacitor storage scheme for short-term storage of the voltage or charge waveform. These devices provide variable maximum delay times without signal attenuation and with delay-to-risetime ratios of up to 102 to 103. A vector array of switched capacitor analog storage elements may be arranged in a ring-buffer topology, with the number of switched capacitor elements ranging from between about 10 and about 105. Two internal counters incremented by a common clock keep track of the variable delay between an input signal and an output signal.

Abstract: A delay circuit is disclosed which includes first level transition unit for receiving an input signal having more than two different logic levels and varying the pulse width of the signal, and second level transition unit connected with the first level transition unit for varying a pulse width of a signal inputted, whereby the delay circuit delays an output signal from the second level transition unit, wherein said first and second level transition unit includes an inverting unit for inverting an input signal, a MOS transistor having its gate electrode receiving the input signal and its first and second electrodes receiving an output signal from the inverting unit, a resistor connected between the first electrode and the second electrode, and a capacitor connected between the second electrode and a ground.

Abstract: An adjustable delay circuit, for a logic input signal, comprises circuitry for charging a capacitance at a first constant current when the logic signal switches to a first logic state; circuitry for discharging the capacitance at a second constant current when the logic signal switches to the second logic state; circuitry for stopping charging and discharging of the capacitance between the moment when the voltage across the capacitance reaches a high threshold or a low threshold and a subsequent switching of the logic signal; and a first comparator connected to switch the state of an output signal when the voltage across the capacitance crosses a third threshold included between the first and second thresholds.

Abstract: Apparatus and method for aligning signal transition edges in high-speed complementary metal-oxide-semiconductor (CMOS) integrated circuits and other electronic circuits, systems and devices. A transition edge alignment circuit in accordance with the invention includes first and second inverter chains, each having a plurality of series-connected inverters. A first signal, which may be a digital logic signal, is applied to an input of the first inverter chain. A second signal, which may be a clock signal used to latch the logic signal in an integrated circuit, is applied to an input of the second inverter chain. The inverter chains may be constructed such that the inverters of the second chain have a stronger drive capability than the corresponding inverters of the first chain. Capacitive coupling is provided between outputs of inverters of the first chain and outputs of corresponding inverters of the second chain.

Abstract: A clock driver circuit (100) comprises an input (102) for a reference clock signal. A filter (106) is connected to the input to receive the reference signal and output a filtered signal. A complementary FET driver circuit (108) having a cross-over threshold is coupled to the filter to receive the filtered signal and output a conditioned clock signal.

Abstract: The present invention has an object to provide an inverted amplifying circuit with improved accuracy of output and reduced electric power consumption. In an inverted amplifying circuit according to the present invention, a MOS switch is connected between pMOS and nMOS of a CMOS inverter and between balancing resistances. The MOS switch is opened when the inverted amplifying circuit does not work.