9results about "Counting chain asynchronous pulse counters" patented technology

The application relates to a random clock generation method and device against side channel attacks, wherein the method comprises the following steps: S1, selecting a reference clock as an input clock of a first round of multi-path frequency multiplication to obtain frequency multiplication clocks with different frequency multiplication coefficients; S2, randomly selecting a frequency multiplication clock from the frequency multiplication clocks, performing spur filtering, and then outputting the frequency multiplication clock as a system clock; S3, performing multi-path frequency division on the randomly selected frequency multiplication clock to obtain frequency division clocks with different frequency division coefficients; S4, randomly selecting a frequency division clock from the frequency division clocks, and performing multi-path frequency multiplication on the frequency division clock as an input clock of a next round of multi-path frequency multiplication to obtain frequency multiplication clocks with different frequency multiplication coefficients; and S5, repeating steps S2 to S4, and obtaining a system clock with various and random frequencies through multiple rounds of iteration. The application effectively improves the side channel attack protection effect.

An apparatus includes a counter having a clock input, a count value input, a third input, and an output. A multiplexer has a first input, a second input, a selection input, and an output. A delay circuit has a first input coupled to the clock input of the counter, a second input coupled to the output of the counter, a first output and a second output. The first output is coupled to the first input of the multiplexer, and the second output is coupled to the second input of the multiplexer. A fractional control circuit has a first output coupled to the selection input of the multiplexer and has a second output coupled to the third input of the counter.

A semiconductor device according to this disclosure includes: a comparator circuit; a counter circuit; and a latch circuit that stores a count value of the counter circuit at a timing when an output signal of the comparator circuit changes, the counter circuit includes: a multiphase signal generator; and a plurality of flip-flop circuits including a first-stage flip-flop and second-stage and subsequent flip-flops, the first-stage flip-flop takes in an inverted signal of an output signal of a flip-flop in a final stage and each of the second-stage and subsequent flip-flops takes in an output signal of a flip-flop in a preceding stage in synchronization with each of the plurality of clock signals, and an output signal of each of the plurality of flip-flop circuits is output as a count signal of the count value.

The embodiment of the present disclosure provides a counting circuit, comprising: a clock source, a clock control unit and N output units; wherein N is a positive integer. The clock control unit generates a clock control signal according to a clock signal output by the received clock source and output values of the first output unit to the Mth output unit, and outputs the clock control signal to clock input ends of the M+1th output unit to the Nth output unit, wherein the clock control signal has a first signal value and a second signal value with different signal values. The M+1th output unit to the Nth output unit latch when the received clock control signal switches from the second signal value to the first signal value; and keep the current state value unchanged when the received clock control signal is the second signal value.

The invention relates to the field of integrated circuits, and discloses a programmable 0.5-frequency-division frequency divider which comprises a programmable integer frequency divider, a coding circuit, a sampling circuit and a selection circuit. The encoding circuit generates a synchronous control signal using a preliminary output of the integer frequency divider itself. In the 0.5 frequency division mode, the circuit periodically switches the frequency division ratio of the frequency divider between N and N + 1, and synchronously switches the selection signal of the post-stage sampling circuit, so that the selection signal alternately selects between the rising edge sampling result and the falling edge sampling result of the input clock. According to the scheme, the structure is simple, only one programmable integer frequency divider is needed, the chip area and the design complexity are remarkably reduced, and meanwhile the development rhythm of the circuit is accelerated through robust internal time sequence control.

An integrated circuit is provided for processing data in a functional mode and testing the integrated circuit in a scan mode. The integrated circuit comprises a processing unit, a digital function block, an asynchronous counter, an asynchronous counter test stage, a comparator. The processing unit is configured to process and store data in the functional mode of the integrated circuit based on a system clock. The digital function block is implemented by registers and N scan flip-flops, each of which is connected to the system clock. The asynchronous counter is implemented by M flip-flops connected in a chain. The asynchronous counter test stage is configured to reset count data and store test data in the digital function block in preparation for testing the asynchronous counter in a scan mode of the asynchronous counter.

The objective is to provide a clock modulation circuit that can measure the characteristics of a clock with greater precision. [Solution] The clock modulation circuit of the embodiment includes a clock output circuit, a multiple frequency divider circuit that receives a clock from the clock output circuit and has a plurality of frequency divider circuits that divide the clock, and a frequency divider control circuit that controls the timing of the start of frequency division for each of the plurality of frequency divider circuits and controls the phase difference between at least one pair of output signals of the plurality of frequency divider circuits based on the period of the clock.

The utility model provides a frequency divider, a multimode frequency divider, a phase-locked loop circuit, a chip and electronic equipment. The frequency divider comprises a first latch, a second latch, a third latch and a fourth latch which are in feedback cascade connection, the first AND logic circuit is respectively connected with the first latch, the second latch and the fourth latch; the second AND logic is connected between the second latch and the third latch; the third AND logic circuit is connected between the third latch and the fourth latch; and a delay circuit connected with the output end of the second latch, wherein the frequency divider generates an output frequency-divided clock signal through the delay circuit. According to the scheme of the invention, the structure of the frequency divider is optimized, so that the output delay time of the first-stage frequency division module in the multi-modulus frequency divider during signal output is improved, the situation that the signals are sampled by mistake in the subsequent sampling and frequency division process of the frequency division modules is avoided, and the problem that the frequency division ratio is wrong under continuous frequency division change is solved.

The present application provides a clock phase control circuit and a clock phase control method. The clock phase control circuit comprises a frequency divider, a multiplexer and a controller. The frequency divider receives a first clock signal and outputs a plurality of second clock signals. The multiplexer receives the plurality of second clock signals and outputs one of the plurality of second clock signals. The controller is coupled to the frequency divider and the multiplexer. When the controller receives an interrupt signal, the controller outputs a selection signal to the multiplexer according to the interrupt signal. The multiplexer outputs another one of the plurality of second clock signals according to the selection signal. The clock phase control circuit and the clock phase control method of the present application can switch the clock signal appropriately to output a clock signal with appropriate clock frequency.