Agere Systems Inc.

International Rectifier Corporation

Infineon Technologies Americas Corp.

Agere Systems Guardian Corp.

Chil Semiconductor Corporation

Gary D Polhemus

Robert T Carroll

Hrvoje Jasa

Donald J Desbiens

Kenneth Patrick Snowdon

Christopher John Abel

Patrick J Quirk

Matthew Blaha

Anthony B Candage

John E Scoggins

Robert J Kapuschinsky

Marc J Loinaz

Alan Leon Ellis

According to example configurations herein, a leadframe includes a first conductive strip, a second conductive strip, and a third conductive strip disposed substantially adjacent and substantially parallel to each other. A semiconductor chip substrate includes a first array of switch circuits disposed adjacent and parallel to a second array of switch circuits. Source nodes in switch circuits of the first array are disposed substantially adjacent and substantially parallel to source nodes in switch circuits of the second array. When the semiconductor chip and the leadframe device are combined to form a circuit package, a connectivity interface between the semiconductor chip and conductive strips in the circuit package couples each of the source nodes in switch circuits of the first array and each of the multiple source nodes in switch circuits of the second array to a common conductive strip in the leadframe device.

Electrical connectivity for circuit applications

During operation, a protection circuit receives an input voltage representative of current delivered by a power supply phase to a load. In one configuration, the input voltage is received as the voltage across respective drain-source nodes of a synchronous switch (low side switch) disposed in a power supply. The protection circuit selectively controls conveyance of the input voltage so that damaging transient voltages on the input voltage are not passed to a downstream sampling circuit. The sampling circuit includes a capacitor circuit to store the sample of the input voltage. During operation, the sampling circuit utilizes the input voltage conveyed by the input voltage circuit to charge the capacitor with a sample voltage representative of the current. Because the sampling circuit is protected from the damaging transient voltages via the protection circuit, the sampling circuit as well as other downstream circuitry can be fabricated from a type of transistors other than those used in the input voltage circuit to facilitate more accurate current calculations using a small sized capacitor to store the sample of the input voltage.

Current sensing in a power supply

According to example configurations herein, a leadframe includes a connection interface. The connection interface can be configured for attaching an electrical circuit to the leadframe. The leadframe also can include a conductive path. The conductive path in the leadframe provides an electrical connection between a first electrical node of the electrical circuit and a second electrical node of the electrical circuit. Prior to making the connection between the electrical circuit and the leadframe, the first electrical node and the second electrical node can be electrically isolated from each other. Subsequent to making connection of the electrical circuit with the leadframe, the conductive path of the leadframe electrically connects the first electrical node and the second electrical node together. Accordingly, the leadframe provides connectivity between nodes of an electrical circuit in lieu of having to provide such connectivity at, for example, a metal interconnect layer of an integrated circuit device.

A control circuit generates an output based on the first signal and the second signal by encoding the output to be a multi-state signal having at least three states. A magnitude of the multi-state signal generated by the controller varies depending on binary states of the first signal and the second signal. The controller utilizes the output (i.e., the multi-state signal) to control a switching circuit. A driver circuit receives the output generated by the control circuit. In one embodiment, the multi-state signal has more than two different logic states. The driver decodes the multi-state signal for generating signals to control switches in the switching circuit. One signal generated by the driver circuit is a pulse width modulation signal; another signal generated by the driver circuit is an enable/disable signal.

Multi-level signaling

Methods and apparatus are provided for programmable active inductance. The disclosed active inductor devices provide a tunable bandwidth with improved linearity. The disclosed active inductors have a variable frequency response corresponding to a variable inductance of the active inductor. The active inductor comprises a variable resistive circuit having an effective resistance, wherein the variable resistive circuit is comprised of at least one resistor that can be selectively bypassed in the variable resistive circuit to vary the effective resistive. The active inductor has an inductance that can be varied by varying the effective resistance.

Methods and apparatus for programmable active inductance

Embodiments of the invention include an apparatus and method for continuously calibrating the frequency of a clock and data recovery (CDR) circuit. The apparatus includes a delay arrangement that generates a gating signal, and a gated voltage-controlled oscillator that is enabled by the gating signal. The gated voltage-controlled oscillator generates a recovered clock signal that is based on the data signal input to the CDR circuit. The apparatus also includes a frequency control loop that continuously calibrates the gated voltage-controlled oscillator in such a way that the frequency of the clock signal generated by the gated voltage-controlled oscillator continues to be one half of the period of the data bits in the input data signal and the clock signal remains synchronized to the center of the data state transitions of the input data signal. Alternatively, a secondary frequency control loop adjusts the amount of delay in the frequency control loop.

Apparatus and method for calibrating the frequency of a clock and data recovery circuit

A direct calibration technique significantly tightens a tolerance band between multiple voltage controlled oscillators (VCOs), to correct for slight frequency mismatch between the multiple VCOs. The tightened tolerance band enhances the bit error rate (BER) and/or lengthens the possible consecutive identical digits (CIDs) length, and is particularly useful in integrated circuit applications. A Frequency Locked Loop (FLL), an accumulator, and a DAC are implemented to form a calibration loop that becomes far more digital in nature than a PLL, permitting greater embedded circuit test coverage and ease of integration in VLSI digital technologies. A frequency calibrated loop with digital accumulator and DAC in lieu of a PLL with associated charge pump integrator eliminates the need for large integrated capacitors, sensitivity to drift due to the leakage currents associated with deep sub-micron technologies, and embedded analog voltages which generally cannot be tested.

Burst mode clock and data recovery frequency calibration

A differential voltage-controlled oscillator (VCO) employs at least two pairs of varactors, each pair of varactors driven with a corresponding differential control voltage, to generate a differential oscillating waveform. The capacitance of each pair of varactors adds to form the total capacitance of an inductor-capacitor (LC) tank circuit of the VCO, which determines an oscillation frequency of the differential oscillating waveform of the VCO. One differential control voltage controls a capacitance of the first varactor pair for a relatively coarse adjustment of the oscillation frequency, and the other differential control voltage controls a capacitance of the second varactor pair for a relatively fine adjustment of the oscillation frequency.

Dual differential LC voltage-controlled oscillator

A phase detector (PD) generates an up/down signal based on the phase error between data and clock signals input to the phase detector. A voltage controlled oscillator (VCO) generates the clock signal. The up/down signal is applied to a proportional charge pump and a truncated version of the up/down signal is applied to an integral charge pump. The proportional charge pump generates a first voltage for a first time period across a resistor based on the up/down signal, while the integral charge pump generates a second voltage for a second time period across a capacitor based upon the truncated version of the up/down signal and the sampling rate of the data signal by the PD. The second time period is less than the first time period. The first and second voltages are combined and applied to the VCO to drive the clock signal to synchronization with the data.

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Sebago, ME, United States of America

Gary D Polhemus