Performance measuring circuitry, for determining relative operational performance attributes of different types of a class of semiconductor component disposed on a semiconductor die, includes a first oscillator circuit including a plurality of first circuit element modules having a first circuit topology. The first oscillator circuit provides a first performance indication indicative of a collective performance attribute of all types of components in the class. A second oscillator circuit separate from the first oscillator circuit includes a plurality of second circuit element modules having a second circuit topology, and provides a second performance indication responsive to different contributions from different types of components in the class. A comparison circuit receives outputs of the first and second oscillator circuits and determines the relative performance characteristic of the different types of components. Dice may be binned according to performance, for use in assembly of operational circuits with different performance characteristics.

A phase-locked loop circuitry (200) having low variation transconductance design comprises a voltage controlled oscillator structure (308) to provide an output signal (Fosc) having an oscillation frequency. The voltage controlled oscillator structure (308) comprises a voltage-to-current converter circuit (312) and a current controlled oscillator circuit (314). The voltage-to-current converter circuit is designed with a low variation transconductance. The voltage-controlled oscillator circuit (200) has a characteristic curve being independent of different PVT (processes, supply voltages and temperature) conditions to ensure that the phase-locked loop circuitry (200) is stable under different PVT condition.

A stabilized oscillator which comprises a ring oscillator with an odd number of inverters. The output of an inverter is driving a capacitor and the input of the a next inverter. A feedback element is configured for generating a first and a second current with a fixed current ratio between both, and for applying the same voltage over the ring oscillator as over a resistor which is connected in parallel with a current compensator. The first current goes through the parallel connection, the second current goes through the ring oscillator. The current compensator is configured such that the ratio of the current through the current compensator and a parasitic current component of the second current is substantially equal to the ratio of the first and second current.

A method of generating precise and PVT-stable time delay or frequency using CMOS circuits is disclosed. In some implementations, the method includes providing a reference voltage using a resistive module at a positive input terminal of an operational amplifier, coupling gates of a pair of p-type metal oxide semiconductor (pMOS) transistors and a compensation capacitor to an output terminal of the operational amplifier to generate a first bias signal, and coupling a pair of n-type metal oxide semiconductor (nMOS) transistors to a negative terminal of the operational amplifier to generate a second bias signal at the negative terminal, wherein the pair of nMOS transistors is substantially the same as a pair of nMOS transistors in the CMOS delay circuit.

Methods and systems are described for generating multiple phases of a local clock at a controllable variable frequency, using loop-connected strings of active circuit elements. A specific embodiment incorporates a loop of four active circuit elements, each element providing true and complement outputs that are cross-coupled to maintain a fixed phase relationship, and feed-forward connections at each loop node to facilitate high frequency operation. A particular physical layout is described that maximizes operating frequency and minimizes clock pertubations caused by unbalanced or asymmetric signal paths and parasitic node capacitances.

A method comprises: using a plurality of gain stages cascaded in a ring topology to form a ring oscillator configured to output an oscillation signal; controlling a supply voltage of said ring oscillator using a low-speed DAC (digital-to-analog converter) in accordance with a coarse control word; providing a capacitive load at an inter-stage node of said ring oscillator using a varactor array controlled by a control voltage array; establishing said control voltage array using a high-speed DAC array in accordance with a fine control word; adjusting the coarse control word upon a start-up to make an oscillation frequency of said oscillation signal approximately equal to target value; and adjusting the fine control word in a closed loop manner in accordance with a detection of a timing error of said oscillation signal.

An electronic device comprises a regulator, and an oscillator and a resistor coupled to the regulator. The electronic device further comprises a feedback controller that includes a differential amplifier coupled between the oscillator, the resistor, and the regulator. The feedback controller is configured to apply a control voltage to the regulator in response to a resistor voltage upon the resistor and an oscillator voltage upon the oscillator. The feedback controller can be coupled to control a substantially equal voltage upon the resistor and the oscillator.

A voltage-controlled ring oscillator (VCRO) and a VCRO-based sigma delta modulator having capability of enabling and disabling the VCRO cells. A VCRO includes a plurality of inverters coupled in a ring and a transition detector. The transition detector detects a transition of a first inverter and sends a control signal to enable a second inverter if the transition of the first inverter is detected. The transition detector may include a comparator configured to compare an input and an output of an inverter(s) to detect the transition of the first inverter and a latch configured to hold the control signal until it is reset.

In one form, an analog-to-digital converter (ADC) includes first and second ring-oscillator ADCs, a modulus subtractor, and a decimation filter. The first and second ring-oscillator ADCs are responsive to true and complement input voltages, respectively, have outputs for providing first and second digital phase signals, respectively, each having a first predetermined number of bits sampled at a first frequency. The modulus subtractor subtracts the second digital phase signal from the first digital phase signal to provide a phase difference signal. The decimation filter differentiates the phase difference signal at a second frequency lower than said the frequency to provide a frequency signal proportional to a differential voltage between the true input voltage and the complementary input voltage, and decimates the frequency signal to provide a digital code having a second predetermined number of bits greater than the first predetermined number of bits.

A frequency divider circuit includes an oscillator comprising a plurality of delay elements coupled in series with each other, a first coupling circuit coupled to a first oscillator node and including a control terminal to receive a first retiming signal, and a first multiplexer including inputs coupled to receive the input signal and a complementary input signal, a control terminal coupled to a second oscillator node, and an output to provide the first retiming signal. The first multiplexer may be configured to alternate between injecting the input signal into the first oscillator node based on rising edges of the input signal and injecting the input signal into the first oscillator node based on falling edges of the input signal in response to a logic state of an oscillation waveform appearing at the second oscillator node.