39 results about "Dual-modulus prescaler" patented technology

A system may include a control unit and a dual modulus prescaler. The control unit may generate a modulus control signal. The dual modulus prescaler may be configured to divide the frequency of an input signal by Q when the modulus control signal has a first value and to divide the frequency of the input signal by (Q+V) when the modulus control signal has a second value. Q is an irreducible fraction. The sum (Q+V) may be an integer or a fraction. The dual-modulus prescaler includes several clocked storage units (e.g., flip-flops) that are each clocked by a respective one of several equally spaced phases of the input signal. Each clocked storage unit operates in a toggle mode.

The invention discloses a True Single-Phase Clock (TSPC) 2/3 dual-mode prescaler with a high speed and low power consumption. The TSPC 2/3 dual-mode prescaler comprises six-stage dynamic phase inverters, a D trigger DFF1 in a TSPC structure which is formed by serially connecting a first-stage dynamic phase inverter, a second-stage dynamic phase inverter and a third-stage dynamic phase inverter and a D trigger DFF2 in a TSPC structure which is formed by serially connecting a fourth-stage dynamic phase inverter, a fifth-stage dynamic phase inverter and a sixth-stage dynamic phase inverter. The TSPC 2/3 dual-mode prescaler with the high speed and the low power consumption, disclosed by the invention, removes an AND gate and an OR gate in the traditional TSPC 2/3 dual-mode prescaler structure and directly sends outputs of the first D trigger to the fifth-stage dynamic phase inverter in the second D trigger to control pre-charge from the fifth-stage dynamic phase inverter to a node P2 and delay high electric level output by the 2/3 dual-mode prescaler for one more clock period. Therefore, three-way frequency division operation is realized and working speed for the three-way frequency division of the 2/3 dual-mode prescaler is improved.

The invention discloses a moisture measurement method and device of a vertical section of farmland soil. The device is characterized by comprising a mounting pipe sleeve, a hollow cylindrical electrode, an insulating pipe column, a base band coaxial cable, a liquid-phase hollow water column, a resisting plate and a core processor; the moisture measurement device of the vertical section of the soil is controlled by a voltage-controlled oscillator to generate a high-frequency oscillation signal; a low-frequency square wave signal is obtained through silicon epitaxy high-frequency and low-noise amplitude amplification, and shaping and frequency division of a dual-modulus prescaler; accurate sensing of the volume moisture content of the soil is realized through a mathematical model between the frequency and the volume moisture content of the soil. A cylindrical stereoscopic type multilayered structure is adopted, and a moisture dynamic determination fitting and quantitative inversion technology of the vertical section of the farmland oil is integrated, so that the volume moisture convent of different heights of the vertical section of the farmland oil and the moisture supply amount of the soil of the vertical section are dynamically sensed in real time by utilizing the fewest layers; the moisture measurement method and device has the greatest advantages that the moisture condition of the vertical section of the soil can be continuously sensed in real time, the space integrity is strong and real-time calibration can be realized.

The invention of the "high-frequency CMOS dual/multi modulus prescaler" is a new application in this field. Compared to other transistors which have CMOS technology, this invention has a greater potential for high frequency operations. Additionally, it has a low-power consumption property and can be easily integrated with CMOS technology. We propose a general construction of the prescaler which can be applied to dual-modulus prescaler. First, a divide-by-3/4 dual-modulus prescaler and a divide-by-4/5 one are presented. Consequently, a general dual-modulus prescaler is developed based on the same technique. Moreover, a general multi-modulus prescaler will also be achieved. The operating frequency can be up to 1 GHz for the proposed dual/multiple modulus prescalers which are fabricated in a 0.8- mu m SPDM CMOS technology.

A high speed dual modulus prescaler aims to be used on a frequency synthesizer of wireless communication systems to divide frequency of input signals. The high speed dual modulus prescaler includes a first D flip-flop, a second D flip-flop and a main control transistor. The main control transistor switches connection of the first D flip-flop and second D flip-flop. The main control transistor provides an OR gate state and an AND gate state to form an OR gate circuit and an AND gate circuit in the prescaler. Thereby the number of transistors in the prescaler can be reduced to increase operation speed and lower power consumption.

In the dual modulus prescaler circuit, an output terminal of the first multi-input logic gate circuit is connected to a data input terminal of a first D flip-flop circuit; output terminals of the first to (n-2)th D flip-flop circuits are, respectively, connected to data input terminals of the second to (n-1)th D flip-flop circuits; output terminals of the (n-1)th and nth D flip-flop circuits are connected to input terminals of the first multi-input logic gate circuit; the second multi-input logic gate circuit is connected to the output terminal of the (n-1)th D flip-flop circuit and receives a switching signal; and an output terminal of the second multi-input logic gate circuit is connected to a data input terminal of the nth D flip-flop circuit. Moreover, all the aforementioned connections are connections using differential signals.

A dual-modulus prescaler circuit for a frequency synthesizer comprises a plurality of asynchronous dividers-by-two connected in series, a phase selector unit (11) between two dividers-by-two (10, 12) and a control unit (13) for supplying control signals (S0, S1, S2) to the selector unit as a function of a selected mode. Said selector unit receives four signals phase shifted by 90° in relation to each other from a master-slave first divider and supplies a selected one of the four phase shifted signals. The control signals (S0, S1, S2) are supplied to the selector unit for selecting one of the four phase shifted signals (F2) at the output in a particular division period. As a function of the control signals supplied by the control unit (13) in one selected of the modes, the selector unit effects phase switching in each division period between two phase shifted signals selected by each branch. The second phase shifted signal i in phase lead of 90° in relation to the first phase shifted signal.

The invention relates to a dual-mode 4/4.5 dual-modulus prescaler circuit, which belongs to the phase-locked frequency synthesis technology field in IC design, and comprises four two-input AND gates, two rising edge D-triggers, two descending edge D-triggers, two flip-latches and two two-input signal selectors, wherein, two of the two-input AND gates, the rising edge D-triggers, the two descending edge D-triggers and one two-input signal selector form a prescaler logic circuit; two two-input AND gates, the two flip-latches and one two-input signal selector form a loop termination logic circuit; and the prescaler logic circuit and the loop termination logic circuit realize 4 frequency division or 4.5 frequency division under the action of external control signals. The dual-mode 4/4.5 dual-modulus prescaler circuit reduces the step length of frequency dividing ratio and the quantum step of a Delta-Sigma modulator to reach 0.5, increases the system resolution, reduces the phase noises produced by the Delta-Sigma modulator, and can increase the loop bandwidth and accelerate the system generated time with the same phase noises being kept.

A high speed CMOS phase locked loop (PLL) (10) includes a three-state phase detection circuit having a frequency phase detector (12) coupled to a charge pump (14) for monitoring the phase differences between a reference frequency signal and a divided output frequency signal. The PLL can further include a loop filter (16)coupled to the three-state phase detection circuit, a VCO (18) coupled to the output of the loop filter, a VCO buffer (22) coupled to the output of the VCO for providing an output frequency signal, and a dual modulus prescaler (28) having a synchronous counter (27 and 29) using feedback among D flip-flops (30 and 32) for generating the divided output frequency signal.

Disclosed is a Dual-Modulus Prescaler (DMP) dividing an input signal into an output signal, comprising: a synchronous counter, including a D-Flip-Flop (DFF), a first NOR-Flip-Flop and a second NOR-Flip-Flop, receiving the input signal, the division ratio thereof being based on an intermediate signal; a control logic, controlling the division ratio of the synchronous counter and selecting the output frequency based on first and second control signals, and outputting the intermediate signal to the synchronous counter; and an asynchronous counter, coupled to the control logic and the synchronous counter, having a chain of five DFFs.

The invention belongs to the technical field of radio frequency communication chips, and particularly relates to a high-speed differential dual-modulus prescaler which is used for a multi-GHz frequency comprehensive phase-locked loop design technology. According to the high-speed differential dual-modulus prescaler, a logic gate of a trigger input end is combined with input-stage clock enable inverters, and a logic gate conversion rule that input and output are in inverse relationships is utilized. By means of latches between differential circuits, high-speed dynamic circuits are converted to high-speed static steady-state circuits. According to the technical scheme, a high-speed and low-power dual-modulus prescaler design technology which is suitable for a novel deep submicron process is provided, and the design requirement of frequency division of a frequency synthesizer and a local oscillator in a wireless radio frequency communication chip at present is effectively met.

The invention discloses a true single-phase clock dual-mode prescaler with high speed and low power consumption. The prescaler comprises a trigger unit consisting of a plurality of static complementary metal oxide semiconductor (CMOS) D triggers, a mode switching control unit and an adaptive power consumption control unit; the static CMOS D triggers are synchronously triggered, the CK ends of the static CMOS D triggers are connected with an input clock, and the D ends of the static CMOS D triggers are connected with the output of the mode switching control unit; the input of the mode switching control unit is connected with a frequency division and mode control end and the output of the trigger unit; and the input of the adaptive power consumption control unit is connected with a module power-off control word and the output of the mode switching control unit. Specific logic is adopted in the D triggers to reduce capacitive load so as to improve the working speed, the current of a true single-phase clock is reduced from milliamperes to microamperes at the same high speed compared with a current mode logic structure, and the power consumption of the dual-mode prescaler is also reduced by 15 to 50 percent through an adaptive power consumption control mode according to total frequency dividing ratio configuration.

The invention provides a TSPC trigger, a dual-mode prescaler and a frequency divider. The TSPC trigger comprises a first-stage structure, wherein the first-stage structure comprises a first transistorand a second transistor, and the size of the second transistor is larger than that of the first transistor, a first end of the first transistor is connected with a power supply, a grid of the first transistor is connected with a clock signal end, a second end of the first transistor is connected with a first end of the second transistor, a second end of the second transistor is grounded, and a grid of the second transistor is connected with a first signal end. Because the first end of the first transistor connected with the clock signal end is connected with the power supply, compared with the prior art, the TSPC trigger has the advantages that the transistor, namely the first transistor, connected with the clock signal end is closer to the power supply, and when the clock signal input bythe clock signal end controls the first transistor to be conducted, the power supply voltage can be transmitted to the output end of the first-stage structure more quickly, so that the working speedsof the TSPC trigger, the dual-mode prescaler and the frequency divider are increased.