Abstract: A synchronizer system and method that can be used with a conventional adjustable delay circuit to preserve a pseudo-synchronous phase relationship between clock signals of different clock domains when the time delay of the adjustable delay circuit from which one of the clock signals is output is changed.

Abstract: A device having power management capabilities and a method for power management, the method includes: providing a clock signal and a supply voltage to at least one component of a device; detecting a timing error; delaying by a fraction of a clock cycle and in response to the detected timing error, a clock signal provided to at least one of the components; and determining a clock signal frequency and a level of the supply voltage in response to at least one detected timing error.

Abstract: A method and system for generating multiple clock signals from a reference clock signal are provided. In one implementation, the system includes a reference clock to generate a reference clock signal having a first frequency, a first prescaler to receive the reference clock signal and generate a first output clock signal having a pre-determined frequency relative to the first frequency of the reference clock signal, and a second prescaler to receive the first output clock signal and generate a second output clock signal having a second pre-determined frequency relative to the first pre-determined frequency of the first output clock signal. The first output clock signal is substantially synchronous to the second output clock signal.

Abstract: A apparatus and method are disclosed for generating one or more clock signals. A clock signal is generated based on pattern signals and a reference clock signal. When the reference clock signal transitions high, the state of a first pattern signal is output, and when the reference clock signal transitions low, the state of a second pattern signal is output. Successive states of the first and second pattern signals, selected according to the reference clock signal, provide the generated clock signal.

Abstract: Apparatus, systems, and methods implementing techniques for converting clock signals are described. A voltage-based input clock signal is received and converted into a current-based clock signal. An electrical current of the current-based clock signal is varied in response to the input clock signal while a voltage of the current-based clock signal remains substantially constant.

Abstract: A tunable multiple frequency source system employing offset signal phasing includes a first frequency source, a phase delay element, and a second frequency source configured to operate concurrently with the first frequency source. The first frequency source includes an input coupled to receive a reference input signal and an output for providing a first frequency source signal. The phase delay includes an input coupled to receive the input reference signal, and an output, the phase delay element operable to apply a predefined phase delay to the input reference signal to produce a phase-delayed input signal. The second frequency source includes an input coupled to receive the phase-delayed input signal and an output for providing a second frequency source signal.

Abstract: A clock signal transmission circuit having a variable initial value for a wait time that is required until a clock signal stabilizes. The clock signal is generated from an original clock signal. The wait time setting unit generates a plurality of wait time signals to wait until the original clock signal stabilizes before providing the clock signal to the internal circuit. A wait time determination unit selects one of the wait time signals and provides the selected wait time signal to a clock control unit. The wait time determination unit includes a data holding circuit which generates a selection signal in accordance with the initial value, a selection circuit which selects one of the wait time signals based on the selection circuit, and an initial value setting circuit enabling the initial value to be varied.

Abstract: A device and method for generating an adjustable chaotic signal are provided. The chaotic signal generation device includes a plurality of triangle pulse train generators which generate a plurality of triangle waves having different frequency cycles, an adder which adds the triangle waves output from the triangle pulse train generators and outputs a noise signal, and a frequency modulator which converts the noise signal to a certain frequency band to output a chaotic signal. Accordingly, the power consumption and cost are reduced and the manufacture of the chaotic signal generation device is simplified due to the components integrated on an IC. Also, a plurality of users can use wireless communications in a particular wireless communications area.

Abstract: A clock generator includes a ring oscillator for outputting a basic signal, a divide-by-N frequency divider for dividing the basic signal by a division ratio N to generate a clock signal having a target frequency, a divide-by-two frequency divider for dividing the clock signal by two when an enable signal is on, a counter for counting the number of pulses of the basic signal for a predetermined period of time, a calculator for calculating the division ratio N, and a comparator for comparing a count value of the counter with a threshold value. When the count value of the counter is less than the threshold value, the comparator turns on the enable signal. Thus, when a temperature of the ring oscillator increases, the frequency of the clock signal is reduced to half the target frequency.

Abstract: An magnetic resonance diagnostic apparatus which includes a main unit and a coil unit, the magnetic resonance diagnostic apparatus including a sampling clock generating unit which generates a sampling clock signal, a sampling clock transmitting unit wirelessly transmits the sampling clock signal, a sampling clock receiving unit which receives the transmitted sampling clock signal, a receiving coil which outputs an electrical magnetic resonance signal in response to a magnetic resonance signal emitted from a subject as electromagnetic radiation, a digitization unit which digitizes, synchronously with the received sampling clock signal, the outputted magnetic resonance signal, a resonance signal transmitting unit which wirelessly transmits the digitized magnetic resonance signal, a resonance signal receiving unit which receives the transmitted magnetic resonance signal, and a reconstruction unit which processes, synchronously with the generated sampling clock signal, the received magnetic resonance signal and t

Abstract: A self-timed clock circuit and method of generating a self-timed clock circuit. The circuit includes means for charging a circuit node in response to an external reset signal; means for discharging the circuit node in response to a trigger signal generated by a photodiode; means for generating a first signal indicating a logic level of the circuit node; means for generating and delaying a second signal indicating the logic state of the circuit node; means for combining the first and second signals to generate a recharge signal; and means for recharging the circuit node in response to the recharge signal.

Abstract: A clock gater includes a first logic circuit that receives an enable signal and that includes first and second subcircuits. The clock gater also includes a latch that shares first and second nodes with the first logic circuit and that includes third and fourth subcircuits. The first logic circuit and the latch receive a clock signal that varies between first and second clock states. The first and third subcircuits pull the first and second nodes, respectively, to a common precharge voltage based on the first clock state in order to pass the clock signal. The second and fourth subcircuits pull the first and second nodes, respectively, to complementary voltages based on the second clock state to pass the clock signal. The first node passes the clock signal or gates the clock signal based on the enable signal.

Abstract: The semiconductor device is provided with a clock signal generation circuit that includes a reference clock signal generation circuit which generates a first reference clock signal, a first counter circuit which counts the number of rising edges of the first reference clock signal by using the first reference clock signal and a synchronizing signal, a second counter circuit which counts the number of rising edges of the first reference clock signal by using an enumerated value of the first counter circuit, a first divider circuit which divides a frequency of the first reference clock signal by using the enumerated value of the first counter circuit and generates a second reference clock signal, and a second divider circuit which divides a frequency of the second reference clock signal and generates a clock signal.

Abstract: The present invention is aimed at providing an output circuit that is of relatively small scale and may perform adjustment to make the output-signal rise slew rate and the fall slew rate equal to each other. An output circuit includes a signal output unit configured to produce at a signal output node a signal that makes transition between a first potential and a second potential, a load circuit having a variable load, and a first switch circuit configured to select one of electrical conduction and non-conduction between the signal output node and the load circuit.

Abstract: In one embodiment of the present invention, a source driver includes a shift register including latch stages each including a level shifter that level-shifts clock signals so that the signals are fed into a set-reset flip-flop as inverted set input signals. Outputs from the set-reset flip-flop are delayed by a hazard preventing circuit and then fed into a level shifter in the next latch stage as enable signals. A delay trimming circuit causes a NAND circuit to perform a NAND operation with respect to outputs obtained by a delay of the outputs by a delay circuit and outputs from the level shifter in the next latch stage, so that a sampling pulse is derived. This allows for provision of a pulse output circuit capable of further trimming delay in output pulses and of securing a sufficient interval between the output pulses.

Abstract: A circuit is provided that includes an input for a clock signal, a random event generator for outputting a random signal, in particular random numbers, a settable delay device that is connected to the input for the clock signal and is connected to the random event generator for the purpose of setting a delay of an edge of the clock signal (clk) by means of the random signal.

Abstract: A synchronous clock generation apparatus including a multiplier for multiplying a horizontal synchronizing signal by a horizontal synchronizing pulse signal to generate multiplication data, a gain variable digital LPF for extracting only DC components from the multiplication data and capable of performing gain adjustment, and a controller for calculating gain adjustment data, lock center frequency setting data, and LPF gain adjustment data based on the correction data. The controller detects an amount of deviation from the lock center frequency and an amount of variation, displaces the lock center frequency and shifts the lock range along the frequency axis to enlarge the apparent lock range when the amount of deviation is large, and reduces the gain to improve lock precision when the amount of variation is small, without expanding bits in the circuit configuration.

Abstract: The present utility model proposes an impulse generator for driving an electronic ballast of a gas discharge lamp, the electronic ballast includes a resonance ignition circuit, characterized in that the impulse generator comprises: a micro-controller for generating a clock frequency signal, a logical time sequence control signal and a control voltage signal; a voltage controlled oscillator, coupled to the micro-controller, for receiving the logical time sequence control signal and the control voltage signal to generate oscillation and output a voltage controlled oscillating frequency signal; a phase comparator for receiving the clock frequency signal and the voltage controlled oscillating frequency signal to perform a logical exclusive-OR operation and output an impulse signal of corresponding frequency, thereby driving the resonance ignition circuit to generate a resonance voltage. In addition, the utility model also proposes an over-voltage protection circuit used for the electronic ballast.

Abstract: Clock multiplexing techniques generate an output clock signal by detecting edges of a selected input clock signal and toggling the output clock signal based on detected edges of the selected input clock signal. Toggle signals are generated based on detected edges of the selected input clock signal. Toggle signals are used to control when the output clock signal is to toggle high or low. A latch holds the state of the output clock signal in its current state until changed by receipt of a toggle signal. Switching from use of a first clock signal to use of a second clock signal occurs regardless of whether the first input clock is operating. A delay is introduced that prevents glitches in the output clock signal that are less than one half clock period of the next selected input clock signal in duration.

Abstract: Disclosed is a circuit for generating pulses for a semiconductor apparatus. The circuit for generating pulses for a semiconductor apparatus includes a temperature sensor, a temperature signal decoder, and a pulse generator. The temperature sensor senses the temperature of a memory chip and converts the temperature into a digital code combination so as to output a plurality of temperature information signals. The temperature signal decoder decodes the plurality of temperature information signals so as to output a delay control signal. The pulse generator outputs an overdriving pulse signal in response to a sense amplifier driving signal and the delay control signal.

Abstract: A signal processing apparatus is provided, which generates a data signal having a signal waveform corresponding to a first bit value of a signal waveform transitioning from a high level to a low level or a signal waveform transitioning from a low level to a high level, a pre-transition signal level corresponding to a second bit value of one of a plurality of high levels and a plurality of low levels, and a post-transition signal level corresponding to a third bit value of the other.

Abstract: An Automatic System Clock Detection System (ASCDS) may provide integrated circuits (ICs) with the capability to detect the frequency of an external crystal oscillator or clock source, and adjust the IC's internal PLL accordingly for proper IC operation. The frequency detection and PLL adjustment may be performed without any additional pins on the IC, and/or without requiring any additional external information. The ASCDS may be configured with an internal ring oscillator, which may be generated from standard logic elements, a watchdog counter, and an input clock counter. When the IC comes out of power on reset (POR), the ASCDS may compare the input clock counter with the watchdog counter, and determine the clock frequency of the input clock. It may then set the PLL parameters to ensure correct IC operation.

Abstract: Aspects for program pulse generation during programming of nonvolatile electronic devices include providing a configurable voltage sequence generator to manage verify-pulse and pulse-verify switching as needed during modification operations of a programming algorithm for nonvolatile electronic devices, wherein more efficient modification operations result. In this manner, highly flexible bit sequence generation that can be easily managed by a microcontroller occurs, resulting in a shorter code length, a faster execution time, and ease of reuse in different devices. More particularly, fully compatible voltage sequence generation is introduced that can be applied on the terminals of the flash cells being modified and permits an efficient and time saving management of pulse-verify and verify-pulse switching.

Abstract: Provided is a pulse control device is maintained with a constant pulse width corresponding to a change of process or temperature. The pulse control device comprises a fuse set for selectively outputting a delay increase signal and a delay decrease signal that have a different state based on a cutting or non-cutting state of a fuse on which information on a change of process is programmed, and a pulse generator provided with a plurality of delay cells with predetermined time delay for selectively increasing or decreasing the number of the plurality of delay cells depending on the delay increase signal and the delay decrease signal to generate an internal clock with a pulse width corresponding to the number of the increased or decreased delay cells.

Abstract: A multiphase clock generation circuit (111) for generating a multiphase cock signal, a phase subdivision unit (113) for shifting a phase of the multiphase clock signal output from the multiphase clock generation circuit (111), and a clock selection unit (114) for selecting one of clock signals output from the phase subdivision unit (113) are provided. A PLL circuit (120) for receiving an output from a frequency division circuit (115) is further provided. The phase shift carried out by the phase subdivision unit (113) and the selection of the clock signal carried out by the clock selection unit (114) are controlled by a frequency control unit (112) to switch SSC ON/OFF and to change the bandwidth of the PLL circuit (120).

Abstract: A delay-lock loop receives an input clock signal from the output of a programmable divider that receives a reference clock signal. The delay-lock loop includes a voltage-controlled delay line generating a plurality of delayed clock signals having different phases. A plurality of the delayed clock signals are combined to generate a plurality of output signals. During an initialization period, an initialization circuit sets the delay of the delay line to a minimum delay value and then compares this delay value to the period of the input clock signal. Based on this comparison, the initialization circuit programs the programmable divider and adjusts the number of delayed clock signals combined to generate the output signals. More specifically, as the frequency of the reference clock signal increases, the divider is programmed to divide by a greater number, and a larger number of delay clock signals are combined to generate the output signals.

Abstract: The invention relates to a method for producing a time base for a microcontroller and a simple circuit arrangement therefor, which comprises an RC-element having a specific time constant, said element being connected to a connection of the microcontroller. According to said method, the capacitor of the RC element is charged to an initial voltage in a first step, then in a second step, the number of timed impulses is counted until the voltage on the capacitor falls below the initial voltage to a determined percentage of the initial voltage or a voltage threshold value, and then in a third step, the counted number of timed impulses is used as a time base.

Abstract: For the purpose of achieving multiplexing of data signals for the channels of more than four in number in the generating of a frequency-divided clock signal using toggle flip-flop circuits (TFF), while avoiding any possible phase shift relationship between generated frequency-divided clock signals attributed to the indefinite initial state posing the inherent problem of the TFF, there is provided a clock generator circuit comprising a plurality of toggle flip-flop circuits connected in series, capable of outputting a pair of frequency-divided clock signals with different phases; and a delay circuit connected to the toggle flip-flop circuit, capable of outputting a clock signal with a phase shifted with respect to the phases of the pair of frequency-divided clock signal phases by delaying either one or both of the pair of frequency-divided clock signals being outputted from the toggle flip-flop circuits.

Abstract: In a semiconductor device capable of radio communication, a stable clock signal is generated even if a reference clock signal for generating a clock signal has varied frequencies in each cycle. A clock signal generation circuit includes an edge detection circuit that detects an edge of an input signal and generates a synchronization signal, a reference clock signal generation circuit that generates a clock signal which functions as reference, a counter circuit that counts the number of edges of rise of the reference clock signal in accordance with the synchronization signal, a duty ratio selection circuit that selects a duty ratio of a clock signal from a count value, and a frequency division circuit that generates the clock signal having the selected duty ratio.

Abstract: An electronic circuit for performing clock gating on a clock signal supplied to a clock system using both edges, has a non-inverted/inverted signal selector which has an input connected to an input terminal, is fed with the clock signal through the input terminal, and outputs a first signal obtained by non-inverting or inverting the clock signal in response to a control signal; a signal latch which has an input connected to an output of the non-inverted/inverted signal selector, outputs the inputted first signal as a second signal through an output terminal, and latches a state of the second signal in response to an enable signal inputted through an enable terminal; and an input/output comparator which compares the clock signal and the second signal and outputs the control signal to the non-inverted/inverted signal selector such that the first signal agrees with the second signal.

Abstract: An internal clock generator that modulates a high-frequency clock signal to a low-frequency signal to transmit the low-frequency signal if a transmission line for transmitting the high-frequency clock signal is long, and then restores the transmitted low-frequency signal to the high-frequency signal. The internal clock generator includes a first signal generation unit for receiving a first signal having a first frequency and generating a second signal having a second frequency that is lower than the first frequency, and a second signal generation unit for receiving the second signal and generating a third signal having a frequency equal to the first frequency. Here, the third signal is used as a signal for controlling an operating time point of an internal circuit of a synchronous memory device.

Abstract: A signal generation circuit that uses a waveform generation mechanism to generate predetermined waveform(s) when triggered. A triggering mechanism is configured to repeatedly trigger the waveform generation mechanism at times that are dependent on data provided by a data source. The predetermined waveform may be a bandwidth-limited pulse, but might also be a rising edge or a falling edge of a pulse. Various consecutive waveforms may be summed together to thereby formulate a continuous signal. The waveform may have particular characteristics by design.

Abstract: A digitally controlled delay line generates a clock signal. The clock signal can be modulates as a spread spectrum clock signal. In an example embodiment, the programmable delay line has an input for receiving a signal, an output that delays outputting the input signal by a time period programmed into a delay value input. A feedback loop comprising an inverter is coupled between the input and the output of the programmable delay line.

Abstract: A system and method for seamlessly reprogramming clock frequencies includes a phase locked loop (PLL) that generates CPU and double data rate (DDR) clocks. A crystal is used to generate a reference clock. The CPU clock and the reference clock are inputs to a first multiplexer, and the DDR clock and reference clock are inputs to a second multiplexer. In normal operation the multiplexers provide the CPU and DDR clock signal as outputs. To reprogram the clock frequencies and reset the PLL, (1) the reference clock signal is selected to be the output of both multiplexers, so the device is running on the internal reference clock. The mux switching is synchronized with the CPU and DDR clock signals. (2) The PLL is reprogrammed, its internal voltage-controlled oscillator is reset, and the PLL is restarted at the new desired frequency. (3) When the new PLL frequency output is stable, the multiplexers are switched back to the PLL-generated CPU and DDR clocks, synchronously with the reference clock signal.

Abstract: A synchronizer system and method that can be used with a conventional adjustable delay circuit to preserve a pseudo-synchronous phase relationship between clock signals of different clock domains when the time delay of the adjustable delay circuit from which one of the clock signals is output is changed.

Abstract: A transmitter circuit has two mixers that modulate a carrier wave according to an input signal, outputs a signal having information in a phase and an amplitude, detects a DC offset in each of the mixers, and adds a DC voltage that corrects the detected DC offset to the input signal of the mixers. The mixer is a double balanced mixer having two load resistors, and the transmitter circuit has a resistor that is connected between a node of two load resistors and a power supply, a limiter amplifier that amplifies a signal, and a control unit that changes first and second potentials using a signal that is outputted by the limiter amplifier. The first and second potentials become a potential of the DC voltage that corrects the DC offset.

Abstract: A high power electric pulse generator includes a charge storage device, a high voltage source for charging the charge storage device, a first photoconductor element connected to the reference potential and to the storage device, a second photoconductor element connected to the storage device and to a useful load, a first light source for delivering a pulse of light to the first photoconductor, a second light source for delivering a pulse of light to the second photoconductor and a synchronization device for synchronizing the emission delay between the first light source and the second light source. The first photoconductor and the second photoconductor are passive semiconductor elements with a linear regime forming photosensitive switches, with the first and second photoconductors being doped silicon photoconductors.

Abstract: The invention is related to an apparatus and a method for generating an output clock. The method comprises: receiving a transmitted signal comprising at least one data signal and at least one synchronized signal; producing a reference signal according to the synchronization signal; counting the first reference signal according to a free-run clock outputted by a free-run clock generator to produce a counter signal; and generating the output clock according to the counter signal and the free-run clock.

Abstract: A pulse signal generating device includes: an encoder that outputs a pulse with a period corresponding to the speed of an object to be detected; a measurement unit that measures a period of the pulse; a storage unit that stores the measured period; an operation unit that calculates a reasonable period, which is estimated to be statistically reasonable, on the basis of a result of period measurement of a plurality of pulses; a detection unit that detects period abnormalities when the measured period of the measurement unit satisfies a period abnormality condition specified from the reasonable period; and a pulse generating unit that generates a pulse on the basis of the measured period when the period abnormalities are not detected and generates a pulse on the basis of the reasonable period when the period abnormalities are detected.

Abstract: A method and apparatus for clock generation have been disclosed having a selector logic block that controls operation based upon inputs such as analog input(s), digital input(s), a lookup table, and preset value(s), and combinations of such.

Abstract: The present invention provides a way of hysteretic switching for efficiently reducing the heavy switching between two adjacent coarse intervals. The present invention disposes a number of fine intervals to cover a range which is larger than the length of one coarse interval. Each coarse interval comprises some extra fine intervals which are exceeded the boundary of the coarse intervals in one side. The heavy switching will be postponed until the extra fine intervals are used up. In the meantime, the fine calibration unit records the number of extra fine interval which be used. An extra-boundary value will be recorded in the fine calibration unit for determining an initial fine interval in another coarse interval if the heavy switching occurs. It should be noted that the extra-boundary value could be a positive or minus value corresponding to which a forward coarse interval or a backward coarse interval the reference signal drifts into.

Abstract: A reference clock signal generation circuit for generating a reference clock signal for a charge-pump operation which raises or lowers a voltage includes a clock signal generation circuit which generates a reference clock signal having one of first to nth (n is an integer of two or more) frequencies, a wait time setting register in which a value corresponding to a wait time is set, and a frequency setting register in which a value corresponding to one of the first to nth frequencies is set. The clock signal generation circuit generates the reference clock signal having a predetermined frequency in a start period from start of the charge-pump operation to completion of the wait time, and generates the reference clock signal having a frequency corresponding to the value set in the frequency setting register in an operation period after the start period.

Abstract: A clock driver capable of minimizing the ripple of an output signal of a charge pump, and the charge pump including the clock driver are disclosed.

Abstract: A clock synthesis circuit includes a polyphase numerically controlled oscillator, an extraction circuit, and a clock signal generation circuit. The polyphase numerically controlled oscillator generates sets of periodic output signals. Each set of the periodic output signals represents a different phase of a periodic waveform signal. The extraction circuit extracts a most significant bit from each set of the periodic output signals of the polyphase numerically controlled oscillator to generate most significant bits. The clock signal generation circuit converts the most significant bits into a serial bit stream that serves as an output clock signal.

Abstract: The present invention relates to a signal transferring system. The signal transferring system includes a first and second layout paths, and a first and second circuits. Lengths of the first and second layout paths are different. The first and second circuits are used for transmitting and receiving at least two signals respectively. In addition, one of the first circuit and the second circuit includes a compensation circuit for adjusting transmission time of one of the at least two transferred signals or adjusting reception time of one of the at least two transferred signals such that the at least two transferred signals reach a second circuit through the first and the second layout paths at substantially the same time.

Abstract: A clock circuit includes a waveform generator, a comparison module, and a clock signal module. The waveform generator is coupled to generate a waveform based on a reference oscillation. The comparison module is coupled to compare the waveform with a plurality of references to produce a plurality of waveform comparisons. The clock signal module is coupled to generate a clock signal from the plurality of waveform comparisons.

Abstract: Apparatus, systems, and methods are disclosed that operate to adjust power received by a clock distribution network at least partially based on operating conditions of an integrated circuit. Additional apparatus, systems, and methods are disclosed.

Abstract: A clock input filter uses a first programmable low-pass delay element to filter during a low period of an input clock signal and to output a SET signal. The clock input filter uses a second programmable low-pass delay element to filter during a high period of the input clock signal and to output a RESET signal. A latch is set and reset by the SET and RESET signals. The latch outputs a filtered version of the input signal that has the same approximate duty cycle as the input signal. A pair of gates generates a corresponding pair of duty cycle adjusted versions of the input signal. Output multiplexing circuitry is provided to output either the output of the latch, or an increased duty cycle version of the input signal, or a decreased duty cycle version of the input signal, or an unfiltered version of the input signal.

Abstract: A timing generator reduces operation-dependent power consumption (AC component) and noises generated from a clock distribution circuit itself in distributing a clock, and further reduces a skew attributed to the clock distribution. A clock distribution circuit 20 for distributing the clock to timing generating sections 10-l to 10-n has a clock main path 21 connected to a main path buffer 24 and a clock return path 26 connected to a return path buffer 27. A load capacity of the main path buffer 24 is equal to that of the return path buffer 27. Biases of the buffers are the same potential and are generated by a delay locked-loop circuit 30. A propagation delay time of the clock distribution circuit is controlled so as to be an integral multiple of a clock period.

Abstract: A voltage controlled oscillator (VCO) generating an output voltage. The VCO has a transconductance amplifier, a capacitor, a comparator, and a switch. The transconductance amplifier receives an input voltage and outputs an output current and has a control terminal receiving a control voltage. The capacitor is coupled between the output of the transcondcutance amplifier and a signal ground. The comparator has a first input terminal coupled to the output of the transcondcutance amplifier, a second input terminal receiving a reference voltage, and an output terminal providing the output voltage. The switch is coupled between the output of the transconductance amplifier and the signal ground and controlled by the output voltage. Phase lock loops (PLLs) including the VCO, a filter with Gm/C self-tuning and a method of tuning Gm/C are disclosed as well.