A signal compensation method and device, where the method includes receiving a signal sequence suffering from intersymbol interference (ISI), setting a first filtering coefficient to perform filter compensation on the received signal sequence to obtain a first compensation signal sequence, setting a balance filtering coefficient to perform filter compensation on the first compensation signal sequence to obtain a balance compensation result, where the balance filtering coefficient is obtained by adjusting, according to a first compensation error, a balance filtering coefficient set last time, performing sequence estimation on the balance compensation result and outputting the balance compensation result, where the first compensation error adjusts the balance filtering coefficient set to perform filter compensation on the first compensation signal sequence in an iterative manner, thereby effectively compensating for the signal sequence suffering from the ISI, and improving performance of an optical fiber communications system.

Disclosed is a device for detecting the margin of a circuit operating at an operating speed. The device includes: a signal generating circuit generating an input signal including predetermined data; a first adjustable delay circuit delaying the input signal by a first delay amount and thereby generating a delayed input signal; a circuit under test performing a predetermined operation based on a predetermined operation timing and thereby generating a to-be-tested signal according to the delayed input signal; a second adjustable delay circuit delaying the to-be-tested signal by a second delay amount and thereby generating a delayed to-be-tested signal; a comparison circuit comparing the data included in the delayed to-be-tested signal with the predetermined data based on the predetermined operation timing and thereby generating a comparison result; and a calibration circuit determining whether the circuit under test passes a speed test according to the comparison result.

Aspects of the disclosure are directed to sensing integrated circuit (IC) Back End Of Line (BEOL) process corners. In one aspect, an apparatus for sensing IC BEOL process corners includes a ring oscillator including a plurality of ring oscillator stages configured to generate an output waveform with a frequency state; and a shield net circuit including a plurality of shield net stages corresponding to the plurality of ring oscillator stages, the shield net circuit having a toggle input. And, a method includes generating an output waveform with a frequency state using a ring oscillator that includes a plurality of ring oscillator stages; modifying a plurality of ring oscillator stage time delays through a coupling between a plurality of shield net stages and the plurality of ring oscillator stages; and selecting the frequency state using a toggle input of a shield net circuit which includes the plurality of shield net stages.

A method to control aging of a system on chip comprising one or more devices including semiconductor circuit components and at least one aging controller monitoring electrical signals circulating inside the system on chip. The method comprises steps of stressing at least one device of the system on chip by varying hardware parameters related to its operating mode, comparing at least one parameter associated with an electrical signal produced by the at least one device with a reference parameter to determine a difference corresponding to an operating age value of the at least one device, if the operating age value equals or exceeds a threshold age value, determining a stress state value and modifying the operating mode of the at least one device according to the stress state value. A system on chip performing the method is also disclosed.

A value representative of a dispersion of a propagation delay of assemblies of electronic components is determined. A component test structure includes stages of components and a logic circuit connected in a ring. Each stage includes two assemblies of similar components configured to conduct a signal. A test device is configured to obtain values of the component test structure and to perform operations on these values.

Described herein are improved techniques for measuring propagation delay of an integrated circuit that facilitate performing propagation delay measurements on-chip. Some embodiments relate to an integrated circuit comprising programmable oscillator circuitry with a plurality of oscillator stages that are switchable into and out of a delay path based on control signals from a controller, allowing the same programmable oscillator to generate many different oscillator signals according to the received control signals, for the controller to determine a central tendency and/or variance of propagation delay of the integrated circuit. Some embodiments relate to an integrated circuit including programmable delay paths configured to provide an amount of cell delay and an amount of wire delay based on control signals from a controller, allowing the same programmable delay path to generate signals for measuring delays due to cell and wire delays of the integrated circuit.

An integrated circuit (IC) comprising: a margin measurement circuit configured to monitor multiple data paths of the IC and to output, at different times, different ranges of remaining margins of the multiple data paths; a workload sensor configured to output a value representing aggregate operational stress experienced by the IC over a period of time ending at each of the different times; and a processor configured to: (i) compute, based on the value output by said workload sensor, an upper bound and a lower bound of change of the remaining margin of the IC, and (ii) compute upper and lower bounds of a current remaining margin of the IC, based on (a) the upper and lower bounds of change, and (b) a remaining margin indicated by a border between two adjacent ranges outputted by the margin measurement circuit.

Structural testing of a semiconductor integrated circuit (IC), including scanning test patterns or test conditions into internal circuits of the semiconductor IC, for example from a tester device. A timing margin may be measured during the structural test. The margin is measured based on a characteristic of a comparison between a test signal path of the semiconductor IC and a delayed signal path, the delayed signal path being a signal of the test signal path delayed by a variable delay time. An output of the margin measurement sensor may be scanned out, for instance to the tester device.

An integrated circuit includes a data propagation path including a flip-flop. The flip-flop includes a first latch and a second latch. The integrated circuit includes a third latch that acts as a dummy latch. The input of the third latch is coupled to the output of the first latch. The integrated circuit includes a fault detector coupled to the output of the flip-flop and the output of the third latch. The third latch includes a signal propagation delay selected so that the third latch will fail to capture data in a given clock cycle before the second latch of the flip-flop fails to capture the data in the given clock cycle. The fault detector that detects when the third latch is failed to capture the data.

A method for estimating jitter of a clock-signal-under-test includes generating a phase-adjusted clock signal based on an input clock signal and a feedback clock signal using a frequency-divided clock signal. The method includes generating N digital time codes for each phase adjustment of P phase adjustments of the phase-adjusted clock signal using a reference clock signal. Each digital time code of the N digital time codes corresponds to a first edge of a clock signal based on the phase-adjusted clock signal. P is a first integer greater than zero and N is a second integer greater than zero. The method includes generating a jitter estimate using an estimated standard deviation of a distribution of edges of the clock signal based on the N digital time codes for each of the P phase adjustments.