Apparatus comprises source circuitry to provide data items; buffer circuitry having a set of buffer entries to hold one or more data items, provided by the source circuitry, for delivery to one or more destinations within a respective delivery latency, in which a buffer entry holding an initial data item becomes available to hold another data item in response to delivery of the initial data item to its respective destination; and control circuitry to control acceptance of data items from the source circuitry for holding by the buffer circuitry, the control circuitry being configured to control the buffer circuitry to accept a given data item when: (i) a buffer entry is available to hold the given data item and (ii) the delivery latency of data items including the given data item held by the buffer circuitry is such that at least a threshold number of buffer entries may be made available within no more than a threshold availability period.

A circuit receives an input signal having a first level and a second level. A logic circuit includes a finite state machine circuit, an edge detector circuit, and a timer circuit. The finite state machine circuit is configured to set a mode of operation of the circuit. The edge detector circuit is configured to detect a transition between the first and second level. The timer circuit is configured to determine whether the first or second level is maintained over an interval, which starts from a transition detected by the edge detector circuit. The finite state machine circuit is configured to change the mode of operation based on the timer circuit determining that the first or second level has been maintained over the interval.

Apparatuses, and methods, for digital cells power reduction are disclosed. For an embodiment, a first plurality of digital logic cells are directly connected to a Vdd terminal and a Vss terminal that have a potential difference of VDD, a second plurality of digital logic cells being directly connected to a Vdd_R terminal and a Vss_R terminal, wherein a potential difference between the Vdd_R terminal and the Vss terminal is (VDD−X1), and a potential difference between the Vss_R terminal and the Vss terminal is X2, wherein at least one digital logic cell has at least one of (a) an input connected to an output of at least one digital logic cell of the second plurality, or (b) an output connected to an input of at least one digital logic cell of the second plurality. Vdd, Vdd_R and Vss_R terminal voltages can be generated by an array of devices.

Disclosed are a memory interface circuit including an output impedance monitor, which is capable of monitoring and calibrating an output impedance of a driving circuit in real time, and a method of calibrating the output impedance. The memory interface circuit includes a control circuit that outputs a digital transmission signal, a driving circuit that outputs an output signal, based on the digital transmission signal, an output impedance monitor that outputs a pull-up monitoring signal or a pull-down monitoring signal, based on the digital transmission signal and the output signal, and an output impedance calibrator that outputs an impedance monitoring signal, based on the pull-up monitoring signal or the pull-down monitoring signal, and wherein the driving circuit calibrates output impedance based on the impedance monitoring signal.

An impedance calibration circuit includes a first code generation circuit connected to a first reference resistor, and configured to generate a first code for forming a resistance based on the first reference resistor, by using the first reference resistor; a second code generation circuit configured to form a resistance of a second reference resistor less than the resistance of the first reference resistor, based on the first code, and generate a second code by using the second reference resistor; and a target impedance code generation circuit configured to generate a target impedance code based on the first code, the second code, and a target impedance value, and form an impedance having the target impedance value in a termination driver connected to the impedance calibration circuit, based on the target impedance code.

Systems and methods for fault-tolerant threshold circuits used in converting an analog input to a single-bit digital output employ N-modular redundancy of either inverting or non-inverting threshold circuits whose inputs are connected to a single input, and apply majority voting of their outputs to provide correction of transient or permanent faults in up to floor[(N−1)/2] of the individual threshold circuits. Using summation to perform analog majority voting averages the N threshold circuit outputs and provides resilience to single-event transients, but may exhibit an output characteristic having intermediate voltage levels. A digital majority voter having N inputs connected to the outputs of N threshold circuits restores well-defined logic levels and clean hysteresis for Schmitt trigger threshold circuits. A single point of failure at the digital majority voter may be eliminated using an analog majority voter to sum the outputs of three or more redundant digital majority voters.

Embodiments of input supply circuits and methods for operating an input supply circuit are described. In one embodiment, an input supply circuit includes a bias circuit configured to define a voltage threshold in response to an input signal, and an input buffer configured to generate an output signal in response to the voltage threshold. Other embodiments are also described.

The present application discloses a reference voltage circuit with temperature compensation, in which a voltage with a positive temperature coefficient is provided by a current source and an impedance device, and in the meanwhile, a voltage with a negative temperature coefficient is provided by a voltage source. Hereby, the reference voltage circuit according to the invention provides a reference voltage with temperature compensation at an output terminal.

Asynchronous circuits implemented using threshold gate(s) and/or majority gate(s) (or minority gate(s)) are described. The new class of asynchronous circuits can operate at lower power supply levels (e.g., less than 1V on advanced technology nodes) because stack of devices between a supply node and ground are significantly reduced compared to traditional asynchronous circuits. The asynchronous circuits here result in area reduction (e.g., 3× reduction compared to traditional asynchronous circuits) and provide higher throughput/mm.sup.2 (e.g., 2× higher throughput compared to traditional asynchronous circuits). The threshold gate(s), majority/minority gate(s) can be implemented using capacitive input circuits. The capacitors can have linear dielectric or non-linear polar material as dielectric.

Asynchronous circuits implemented using threshold gate(s) and/or majority gate(s) (or minority gate(s)) are described. The new class of asynchronous circuits can operate at lower power supply levels (e.g., less than 1V on advanced technology nodes) because stack of devices between a supply node and ground are significantly reduced compared to traditional asynchronous circuits. The asynchronous circuits here result in area reduction (e.g., 3× reduction compared to traditional asynchronous circuits) and provide higher throughput/mm.sup.2 (e.g., 2× higher throughput compared to traditional asynchronous circuits). The threshold gate(s), majority/minority gate(s) can be implemented using capacitive input circuits. The capacitors can have linear dielectric or non-linear polar material as dielectric.