Abstract: Systems, methods, circuits, and apparatus for managing signal transfers in semiconductor devices are provided. In one aspect, an integrated circuit includes: one or more target units each configured to receive a signal and a plurality of inverting units arranged on signal paths to the one or more target units. For each of the one or more target units, one or more corresponding inverting units of the plurality of inverting units are configured to invert the signal multiple times along a corresponding signal path to the target unit to cause a signal width of the inverted signal received by the target unit to be substantially identical to a signal width of the signal.

Abstract: Aspects of the present disclosure includes a phase shifter that includes a first meandering transmission line having a first input configured to receive a first input signal and a first output configured to provide a first output signal; and a plurality of switches configured to adjust an effective electrical length of the first meandering transmission line. In some embodiments, a method for processing a millimeter wave communication signal in a phase-array antenna includes determining a phase shift appropriate for the millimeter wave communication signal; determining configuration of a plurality of switches configured to adjust an effective electrical length of a first meandering transmission line configured to receive the millimeter wave communication signal; and setting the plurality of switches.

Abstract: The present invention provides a Schmitt trigger circuit in which chattering does not occur in the output of the Schmitt trigger circuit even when it is connected to a communication bus without impedance matching and reflected noise is superimposed on the input signal. The Schmitt trigger circuit includes: a first signal detection circuit; a second signal detection circuit; a latch circuit; a selection signal generation circuit; a first input port; and a first output port. The first signal detection circuit is connected to the first input port, the latch circuit and the selection signal generation circuit. The second signal detection circuit is connected to the first input port, the latch circuit and the selection signal generation circuit. The latch circuit is connected to the selection signal generation circuit and the output port. The selection signal generation circuit includes a delay circuit.

Abstract: A phase correcting circuit includes a delay circuit that receives an input clock signal and delays the input clock signal as much as a first delay time to output an output clock signal to a 0-th node, a first fine tuning circuit, and a second fine tuning circuit. The first fine tuning circuit includes a first terminal connected with the 0-th node, a second terminal receiving a first control signal, and a third terminal, and the second fine tuning circuit includes a fourth terminal connected with the third terminal, a fifth terminal receiving a second control signal, and a sixth terminal connected with a load capacitor. In response to the first control signal, the output clock signal may be further delayed as much as a second delay time shorter than the first delay time. In response to the second control signal, the output clock signal may be advanced as much as a third delay time shorter than the first delay time.

Abstract: Examples describe a duty cycle correction circuit for correcting duty cycle distortion from memory. One example is an integrated circuit for correcting an input clock signal. The integrated circuit includes a first leg circuit and a second leg circuit. The first leg circuit and the second leg circuit both comprise a charging circuit and a discharging circuit. Each charging circuit comprises a first plurality of transistors and each discharging circuit comprises a second plurality of transistors. The charging circuit is coupled to the discharging circuit in series. A number of transistors of the first plurality of transistors in the first leg circuit is different from a number of transistors of the first plurality of transistors in the second leg circuit.

Abstract: Provided is an electronic device configured to be charged with an adapter. The electronic device includes an energy storage unit, a charging unit and a switch unit. The charging unit is configured to receive a bus voltage and output a charging voltage to charge the energy storage unit. The switch unit is electrically coupled in parallel to the charging unit. When the electronic device is coupled to the adapter through a bus interface, the electronic device receives the bus voltage from the adapter, receives a communication signal from the adapter, and selectively turns on or off the switch unit according to the communication signal, and when the electronic device operates in a direct charging mode, the switch unit is turned on to form a direct charging path, to charge the energy storage unit by using the bus voltage.

Abstract: Various implementations described herein are directed to a device with a voltage-controlled oscillator that receives an enable signal, receives a reset signal, and provides internal pulse signals including one or more coarse internal pulse signals and multiple fine internal pulse signals. The device may have a coarse sampler that receives the one or more coarse internal pulse signal and provides a coarse sampled output signal. The device may have a fine sampler that receives the multiple fine internal pulse signals and provides a fine sampled output signal.

Abstract: Systems, methods, and devices are provided for a circuit for generating a pulse output having a controllable pulse width. Systems and methods may include a delay line having a plurality of stages. A delay per stage calculation circuit is configured to determine a per-stage delay of the delay line using a first clock input. A pulse generation circuit is configured to generate the pulse output using the delay line based on the per-stage delay using a second clock input, the second clock input having a lower frequency than the first clock input.

Abstract: A pulse generator of an image sensor includes a delay cell including a plurality of transistors arranged in series between a power voltage and a ground, a stabilization capacitor, and a stabilization switch. The power voltage is supplied to a first terminal of a first transistor disposed first among the plurality of transistors, and a gate terminal of the first transistor is connected to a first node. An input voltage is supplied to a gate terminal of an n-th transistor disposed last among the plurality of transistors, and a ground voltage is supplied to a first terminal of the n-th transistor. The stabilization switch is disposed between a reference voltage input terminal providing a reference voltage and the first node. The stabilization switch is turned on by an input bias control signal to supply the reference voltage to the first node.

Abstract: Various implementations relate to keyboard data communicated from a client device to a remote access manager. For example, the remote access manager may receive the keyboard data via a communication channel. The keyboard data may include key down states. The remote access manager may insert a key up state after each key down state in the received keyboard data to generate modified keyboard data.

Abstract: An architecture is disclosed for an angular rate sensor that includes a duty-cycled phase shifter for generating a clock with high resolution delay for use in synchronized demodulation of a sensor output signal. In an embodiment, a sensor comprises: a mechanical resonator; a drive circuit coupled to the mechanical resonator and operable to actuate the mechanical resonator into resonant vibration; a sense circuit mechanically coupled to the mechanical resonator, the sense circuit operable to generate a sense signal having an in-phase signal component and a quadrature signal component; a demodulator circuit operable to receive the sense signal and a first clock for demodulating the sense signal to separate the in-phase signal component from the quadrature signal component; and a duty-cycled phase shifter coupled to the demodulator, the duty-cycled phase shifter operable to generate the first clock.

Abstract: A reference voltage circuit includes: a depletion type MOS transistor and an enhancement type MOS transistor connected in series, and having gates thereof connected in common, the enhancement type MOS transistor providing a reference voltage from a drain thereof, the depletion type MOS transistor including at least a first depletion type MOS transistor and a second depletion type MOS transistor connected in series; and a capacitor having one end connected to a drain of the first depletion type MOS transistor, and the other end connected to a source of the first depletion type MOS transistor.

Abstract: A comparator includes a first voltage-time conversion circuit, a second voltage-time conversion circuit, and a determination circuit. A first delay unit includes a first falling edge delay circuit that delays a falling edge based on a first input signal, a first rising edge delay circuit that delays a rising edge based on a second input signal, and a first output circuit. A second delay unit includes a second falling edge delay circuit that delays a falling edge based on the second input signal, a second rising edge delay circuit that delays a rising edge based on the first input signal, and a second output circuit.

Abstract: A timer block includes: a digital control block including a mode selector and a register loading a time delay; a counter coupled to the register of the digital control block, wherein the counter loads a counter value corresponding to the time delay based on an operational mode selected by the mode selector and generates a digital output indicating the counter value that is decremented at each clock; and a pulse generator configured to generate a pulse signal based on the counter value of the counter. The timer block is integrated in a programmable logic device (PLD) including a programmable fabric and a signal wrapper that is configured to provide signals between the timer block and the programmable fabric. The operational mode of the timer block is programmably configured using the programmable fabric and the signal wrapper.

Abstract: Described are a system and method to control interface timing and/or voltage operations of signals transmitted between devices. A processor may be coupled through one or more bus interfaces of a bus to one or more corresponding interface timing and/or voltage comparison circuits and corresponding interface timing and/or voltage adjustment circuits.

Abstract: Embodiments are directed to a method of mitigating voltage noise events. The method includes detecting the presence of a voltage noise event at the integrated circuit device. Thereafter, one or more local clock buffers (LCBs) is selected for dampening. A type of dampening is selected for the LCBs. Finally, the dampening is applied to the LCB while the voltage noise event is occurring.

Abstract: Methods and apparatus are provided for trimming one or more clock buffers in a clock and data recovery system in a receiver using a phase shift of the transmit data. At least one clock buffer is trimmed by synchronizing the clock and data recovery system to a transmit clock received from a transmitter. A transmit data signal that is received from the transmitter is then sampled using at least a first latch in the receiver. A phase of the transmit data signal is adjusted in the transmitter until values sampled by the first latch satisfy a first predefined criteria (such as approximately 50% binary ones and 50% binary zeroes). The phase of the transmit data signal is adjusted again to an approximate phase location of a second latch in the receiver, and the transmit data signal is sampled using the second latch. A phase of a clock buffer associated with the second latch is then adjusted until values sampled by the second latch satisfy a second predefined criteria.

Abstract: Apparatuses and methods for delaying signals using a delay line are described. An example apparatus includes a controller configured to in a first mode, set a delay length, and, in a second mode, to determine an initial delay. The apparatus further including a delay line circuit coupled to the controller and includes delay elements. Each of the delay elements includes delay gates that are the same type of delay gate. The delay line circuit is configured to, in the first mode propagate a signal through one or more of the delay elements to provide a delayed signal. The delay line circuit is further configured to, in the second mode, propagate a pulse signal through one or more of the delay elements and provide a corresponding output signal from each of the one or more delay elements responsive to the pulse signal reaching an output of the corresponding delay element.

Abstract: A driving circuit according to the present invention for driving a display apparatus based on display data and a control signal includes: a delay circuit for delaying the input control signal; and a data load section for loading the input display data to the display apparatus at a timing generated by the delayed control signal, where the delay circuit delays the control signal in such a manner that load timing at which the display data is loaded to the display apparatus varies according to fixed timing determined by a constant cycle.

Abstract: A delay circuit for receiving an input signal and generating a delayed output signal. The delay circuit includes a first delay module and a second delay module. The first delay module includes a first delay unit for generating a first delayed signal according to an input signal and a first logic unit, coupled to the first delay unit, for generating a first delayed output signal according to the first delayed signal and the input signal. The second delay module includes a second delay unit for generating a second delayed signal according to the first delayed output signal and a second logic unit, coupled to the second delay unit, for generating the delayed output signal according to the second delayed signal and the input signal.

Abstract: A semiconductor device including a common delay circuit configured to delay an input signal in response to a delay control code to output a first delayed input signal and a second delayed input signal; a first delay circuit configured to delay the first delayed input signal in response to the delay control code and to output a first output signal; and a second delay circuit configured to delay the second delayed input signal in response to the delay control code and to output a second output signal.

Abstract: A delay circuit includes a first flip flop (FF), a transistor connected to the FF, a first resistor capacitor circuit (RCC) coupled to the transistor and between a voltage and a ground, a first comparator for comparing an output of the first RCC and a voltage reference, gate logic coupled to the input line and to an output of the first FF and to a second FF, a second transistor coupled to the second FF, a second RCC coupled to the second transistor and between the voltage and ground, a second comparator for comparing an output of the second RCC and the voltage reference and coupled to the first FF, and output logic coupled to the first and second comparators.

Abstract: Circuits and methods are introduced to allow for timing relationship between a clock signal and a synchronization signal to be observed. The observations may include observing the timing relationship between a capture edge of the clock signal and a transition of the synchronization signal. Based on the observations the timing of the synchronization signal transition may be adjusted. Observing the timing relationship may include providing a delayed synchronization signal and a delayed clock signal. The delayed synchronization signal may provide what happens before the capture edge of the clock signal. The delayed clock signal may provide what happens after the capture edge of the clock signal.

Abstract: One embodiment sets forth a timing calibration technique for on-chip source-synchronous, complementary metal-oxide-semiconductor (CMOS) repeater-based interconnect. Two transition patterns may be applied to calibrate the delay of an on-chip data or clock wire. Calibration logic is configured to apply the transition patterns and then trim the delays of the clock and data wires based on captured calibration patterns. The trimming adjusts the delay of the clock and data wires using a configurable delay circuit. Timing errors may be caused by crosstalk, power-supply-induced jitter (PSIJ), or wire delay variation due to transistor and wire metallization mismatch. Chip yields may be improved by reducing the occurrence of timing errors due to mismatched delays between different wires of an on-chip interconnect.

Abstract: A method for detecting rising and falling transitions of internal signals of an array or integrated circuit. An apparatus used in the method comprises a delay line with a plurality of first to Nth delay elements, latches, and first to Nth groups of logic gates. Each of the first to Nth groups of the logical gates includes an AND gate and a NOR gate. The method determines rising and falling signals based on output signals of the logic gates in the apparatus; in odd numbered groups of the logic gates, the AND gate detects the rising transition and the NOR gate detects the falling transition; in even numbered groups of the logic gates, the AND gate detects the falling transition and the NOR gate detects the rising transition.

Abstract: A method and apparatus for detecting rising and falling transitions of internal signals of an array or integrated circuit. The apparatus comprises a delay line with a plurality of first to Nth delay elements, latches, and first to Nth groups of logic gates. Each of the first to Nth groups of the logical gates includes an AND gate and a NOR gate. The method and apparatus determines rising and falling signals based on output signals of the logic gates; in odd numbered groups of the logic gates, the AND gate detects the rising transition and the NOR gate detects the falling transition; in even numbered groups of the logic gates, the AND gate detects the falling transition and the NOR gate detects the rising transition.

Abstract: A semiconductor device includes a plurality of driving units configured to drive an output node based on an input signal and be on/off controlled based on driving force control codes, respectively, a slew rate control signal generation block configured to generate a slew rate control signal based on the driving force control codes, and a plurality of signal delay units configured to delay the input signal by respectively different delay amounts, transfer resultant signals to the plurality of driving units, and be respectively controlled in their delay amounts based on the slew rate control signal.

Abstract: A circuit includes a delay circuit, a transition detector, a pre-driver circuit, and a controller. The delay circuit includes an input for receiving a signal and an output for providing a delayed version of the signal. The transition detector is coupled to the input of the delay circuit to detect a transition within the signal and to provide a look ahead signal to a detector output. The pre-driver circuit includes an input coupled to the output of the delay circuit, a control input, at least one signal output, and a plurality of a bias outputs. The controller is coupled to the detector output and to the control input of the pre-driver circuit and is configured to control bias signals on a plurality of bias outputs to selectively increase a driving strength of signals and biases applied to an output stage in response to the look ahead signal.

Abstract: Provided is a semiconductor circuit. The semiconductor circuit includes a pulse generator which is enabled by a rising edge of a clock signal and generates a read pulse which varies depending on a voltage of a feedback node; and a sense amplifier which generates a voltage of a dynamic node and the voltage of the feedback node in accordance with a data value of an input signal using the read pulse.

Abstract: Circuits and circuit elements configured to generate a random delay, a monostable oscillator, circuits configured to broadcasting repetitive messages wireless systems, and methods for forming such circuits, devices, and systems are disclosed. The present invention advantageously provides relatively low cost delay generating circuitry based on TFT technology in wireless electronics applications, particularly in RFID applications. Such novel, technically simplified, low cost TFT-based delay generating circuitry enables novel wireless circuits, devices and systems, and methods for producing such circuits, devices and systems.

Abstract: In an embodiment, a delay circuit includes a ring oscillator circuit and a counter circuit. The ring oscillator circuit includes a delay chain having delay elements and configured to generate one of more clock cycles of an oscillator clock signal in response to a clock cycle of a clock signal. The counter circuit includes two counters that are configured to store a count state corresponding to a number of clock cycles of the oscillator clock signal during a single clock cycle of the clock signal. A first buffer is configured to store the number of clock cycles of the oscillator clock signal. The delay circuit includes a buffer to store a bit pattern corresponding to a number of delay elements traversed in a partial clock cycle of the oscillator clock signal in response to the clock cycle of the clock signal based on outputs of the plurality of delay elements.

Abstract: Buffers, integrated circuits, apparatuses, and methods for adjusting drive strength of a buffer are disclosed. In an example apparatus, the buffer includes a driver. The driver includes a pull-up circuit coupled to a supply voltage node and an output node, and also includes a pull-down circuit coupled to a reference voltage node and the output node. A drive adjust circuit is coupled to at least one of the pull-up circuit and the pull-down circuit, with the drive adjust circuit configured to receive a feedback signal and, based at least in part on the feedback signal, adjust a current conducted through the at least one of the pull-up and pull-down circuits.

Abstract: A semiconductor device includes an internal circuit configured to perform a specified operation in response to a predetermined command; a normal data input/output section configured to input/output a normal data synchronized with a center of a source clock, in response to data input/output commands; and a data recovery information signal input/output block configured to receive and store a data recovery information signal synchronized with an edge of the source clock and having a predetermined pattern, in response to either a command of the data input/output commands or the predetermined command upon entry to a data recovery operating mode, and to output the data recovery information signal after the passage of a predetermined time period.

Abstract: A delay circuit for receiving an input signal and generating a delayed output signal. The delay circuit includes a first delay module and a second delay module. The first delay module includes a first delay unit for generating a first delayed signal according to an input signal and a first logic unit, coupled to the first delay unit, for generating a first delayed output signal according to the first delayed signal and the input signal. The second delay module includes a second delay unit for generating a second delayed signal according to the first delayed output signal and a second logic unit, coupled to the second delay unit, for generating the delayed output signal according to the second delayed signal and the input signal.

Abstract: Disclosed herein is a device that includes a plurality of one-shot pulse generation circuits connected in series between an input node and an output node. Each of the one-shot pulse generation circuits receives an input clock signal supplied from previously connected one-shot pulse generation circuit to output an output clock signal to subsequently connected one-shot pulse generation circuit. Both of a rising edge and a falling edge of the output clock signal are controlled based on one of a rising edge and a falling edge of the input clock signal. A time period from one of the rising edge and the falling edge of the output clock signal to the other of the rising edge and the falling edge of the output clock signal being variable.

Abstract: One embodiment sets forth a timing calibration technique for on-chip source-synchronous, complementary metal-oxide-semiconductor (CMOS) repeater-based interconnect. Two transition patterns may be applied to calibrate the delay of an on-chip data or clock wire. Calibration logic is configured to apply the transition patterns and then trim the delays of the clock and data wires based on captured calibration patterns. The trimming adjusts the delay of the clock and data wires using a configurable delay circuit. Timing errors may be caused by crosstalk, power-supply-induced jitter (PSIJ), or wire delay variation due to transistor and wire metallization mismatch. Chip yields may be improved by reducing the occurrence of timing errors due to mismatched delays between different wires of an on-chip interconnect.

Abstract: A semiconductor device includes a division unit configured to divide an oscillation signal and to generate a plurality of divided signals having different division ratios each other, a delay amount determination unit configured to combine an source signal, the oscillation signal, and the plurality of divided signals and to generate a delay amount information signal with information on a given delay amount, and an edge-delayed signal output unit configured to generate at least one edge-delayed signal corresponding to the given delay amount in response to the source signal and the delay amount information signal.

Abstract: In one embodiment a circuit for testing delays is provided. A test signal generator circuit toggles a plurality of output signals 1 through N in sequential order, separating the toggles by a delay period. Each output signal is coupled to an input of a respective one of a plurality of delay circuits. A phase detector circuit is coupled to the delay circuits and is configured to determine the order in which signals output from delay circuits X?1, X, and X+1 are toggled for each delay circuit X. In response to the output signals being toggled in the order X?1 followed by X followed by X+1, the phase comparator circuit is configured to output a first signal indicating correct operation. Otherwise, the phase comparator circuit is configured to output a second signal indicating incorrect operation.

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: The embodiments of the present invention disclose a delay circuit. The delay circuit comprises an inverter, a load capacitor, and a first voltage clamping module, wherein the first voltage clamping module generates a voltage drop configured to prolong the propagation delay time of the delay circuit as the power supply voltage decreases. The power supply dependent delay circuit may have a much larger propagation delay time at low power supply voltage than it at high power supply voltage at the rising-edge or falling-edge of an input signal.

Abstract: A burst order control circuit includes a signal transmitting unit transmitting a second address as first and second signals in response to a mode signal and a first address, a signal delay unit delaying a read command, the first signal, and the second signal to generate a delayed read command, a first delayed signal, and a second delayed signal, a signal generating unit configured to generate a burst signal in response to the first address and generate first and second transmission signals in response to the delayed read command and the first and second delayed signals, and an output unit sorting and outputting a plurality of data in response to the burst signal, the first transmission signal, and the second transmission signal.

Abstract: A delay cell includes a first inverted transistor pair, a second inverted transistor pair and a plurality of delay units. The first inverted transistor pair is used to receive an input signal. The second inverted transistor pair is electrically cross-coupled to the first inverted transistor pair and cross-controlled by the first inverted transistor pair. The delay units are cascaded between the first inverted transistor pair and between the second inverted transistor pair, thereby providing a plurality of signal propagation delays sequentially, wherein the input signal is delayed for a pre-determined time by the first inverted transistor pair, the second inverted transistor pair and the delay units which are operated sequentially, thereby creating an output signal corresponding to the pre-determined time. A digitally controlled oscillator including the aforementioned delay cells is provided.

Abstract: Techniques for performing timing calibration for an integrated circuit (IC) device are described. During operation, a first integrated circuit device transmits a first calibration pattern having differently delayed rising edge transitions with respect to a timing reference. The first integrated circuit device additionally transmits a second calibration pattern having differently delayed falling edge transitions with respect to the timing reference. Next, the first integrated circuit generates a timing offset for transmitting data from the first integrated circuit device. This timing offset is derived from information received from a second integrated circuit device sampling the first calibration pattern and the second calibration pattern.

Abstract: A device includes a plurality of driver circuits coupled to a plurality of bus lines. A first driver circuit of the plurality of driver circuits is coupled to a first bus line of the plurality of bus lines. The first driver circuit includes one of a skewed inverter, a level shifter, a latch, and a sense amplifier configured to produce an output signal that transitions after a first delay in response to a first digital value transition of an input signal from high to low and transitions after a second delay in response to a second digital value transition of the input signal from low to high. The first delay is different from the second delay by an amount sufficient to reduce power related to transmission of signals over the first bus line and over a second bus line in close physical proximity to the first bus line.

Abstract: The propagation delay of a signal through multiple load devices coupled sequentially along a conductor is improved by separating a subset of the load devices that is more distant from the signal source, and coupling the more distant subset to the signal through a fly-over conductor that bypasses the subset that is nearer to the signal source. The technique is applicable to subsets of bit cells in a random access memory (SRAM) coupled to a given word line, or to word line decoder gates coupled sequentially to a strobe signal, as well as other circuits wherein load devices selectable as a group can be divided into subsets by proximity to the signal source. In an SRAM layout with multiple levels, different metal deposition layers carry the conductor legs between the load devices versus the fly-over conductor bypassing the nearer subset.

Abstract: A semiconductor device including a common delay circuit configured to delay an input signal in response to a delay control code to output a first delayed input signal and a second delayed input signal; a first delay circuit configured to delay the first delayed input signal in response to the delay control code and to output a first output signal; and a second delay circuit configured to delay the second delayed input signal in response to the delay control code and to output a second output signal.

Abstract: A reset circuit and a delay circuit are provided. The delay circuit includes a first resistor module, a second resistor module, a switch module and a capacitor module. First terminals of the first and the second resistor modules are coupled respectively to a first voltage and a second voltage. The switch module have a control terminal served as a input terminal of the delay circuit, a first terminal served as a output terminal of the delay circuit, a second terminal coupled to a second terminal of the first resistor module, and a third terminal coupled to a second terminal of the second resistor module. In the delay circuit, the first terminal selectively connected to the second terminal or the third terminal in accordance with the control terminal. The capacitor module couples between the first terminal of the switch module and the second voltage.

Abstract: A delay circuit receives a data input having an input transition and that generates a data output having an output transition. The delay circuit is powered by a voltage source having a voltage. A first delay element is configured to generate a first data signal with a first edge that has a relatively constant delay relative to the input transition irrespective of the voltage of the voltage source. A second delay element is configured to generate a second data signal with a second edge that has a delay relative to the input transition as a function of the voltage of the voltage source. A selection element causes the output transition at the data output to correspond to a latest selected one of the first edge and the second edge. The delay circuit may be employed in a pulse generating circuit.

Abstract: A semiconductor device including a common delay circuit configured to delay an input signal in response to a delay control code to output a first delayed input signal and a second delayed input signal; a first delay circuit configured to delay the first delayed input signal in response to the delay control code and to output a first output signal; and a second delay circuit configured to delay the second delayed input signal in response to the delay control code and to output a second output signal.

Abstract: An electronic oscillation signal generation circuit includes an electronic oscillation circuit, a DC voltage source for providing a DC voltage to the electronic oscillation circuit, a switch for electrically connecting the electronic oscillation circuit to ground when the switch is turned on so as to generate an analog oscillation signal after the switch is turned off, a conversion circuit for converting the analog oscillation signal to a digital oscillation signal, a counter for generating a control signal when the digital oscillation signal reaches a predetermined number of periods, a delay unit for generating a delay signal a predetermined time after a falling edge of the digital oscillation signal is triggered, and a pulse signal generation circuit electrically connected to the counter and the delay unit for generating a pulse signal according to the control signal and the delay signal so as to turn on the switch.