Bae Systems Information and Electronic Systems Integration Inc.

Bae Systems Information and Electronics Systems Integration Inc.

Lockheed Martin Corporation

Ovonyx Inc.

Kenneth R Knowles

Bin Li

David C Lawson

Scott C Willis

Richard Brosh

Daniel Pirkl

Matthew A Gregory

Nandor G Thoma

Michael N Witlin

Arthur Russell Blumen

A ring oscillator circuit is disclosed. The ring oscillator in one embodiment includes an odd number of inverters connected in a loop fashion, a current mirror having a drain of a first transistor connected to the inverters, and a self-biased inverter connected to a drain of a second transistor of the current mirror.

Ring oscillator circuit with frequency stabilization

An apparatus for reducing offset voltage drifts in a charge amplifier circuit is disclosed. The apparatus includes a charge amplifier circuit and a bias current compensation circuit. The bias current compensation circuit supplies bias current to lower any offset voltage drift at the output of the charge amplifier.

Apparatus for reducing offset voltage drifts in a charge amplifier circuit

A read/write circuit for accessing chalcogenide non-volatile memory cells is disclosed. The read/write circuit includes a chalcogenide storage element, a voltage limiting circuit, a current-to-voltage converter, and a buffer circuit. The voltage limiting circuit, which is coupled to the chalcogenide storage element, ensures that voltages across the chalcogenide storage element will not exceed a predetermined value during a read operation. During a read operation, the current-to-voltage converter, which is coupled to the voltage limiting circuit, converts a current pulse read from the chalcogenide storage element to a voltage pulse. By sensing the voltage pulse from the current-to-voltage converter, the buffer circuit can determine a storage state of the chalcogenide storage element.

Read/write circuit for accessing chalcogenide non-volatile memory cells

A digital adaptive power supply interface has two feedback loops, each including a VCO, to automatically compensate for temperature and semiconductor process variations. A first loop compares the system input phase/frequency to a reference voltage that has been converted to a first digital frequency signal by a VCO in the first loop, and generates an analog difference signal. The second loop compares this analog difference with the power supply output voltage, and a VCO in this second loop converts result of this comparison to a second digital frequency signal. The digital frequency signals of the two loops are fed respectively to two registers and the content of the registers are subtracted, one from the other, to generate a digital error signal adjust the power supply output voltage to the input frequency.

Adaptive power controller digital interface

A circuit for accessing a chalcogenide memory array is disclosed. The chalcogenide memory array includes multiple subarrays with rows and columns formed by chalcogenide storage elements. The chalcogenide memory array is accessed by discrete read and write circuits. Associated with a respective one of the subarrays, each of the write circuits includes an independent write 0 circuit and an independent write 1 circuit. Also associated with a respective one of the subarrays, each of the read circuits includes a sense amplifier circuit. In addition, a voltage level control module is coupled to the read and write circuits to ensure that voltages across the chalcogenide storage elements within the chalcogenide memory array do not exceed a predetermined value during read and write operations.

Circuit for accessing a chalcogenide memory array

An SEU immune logic architecture includes a dual path logic gate coupled to a dual to single path converter. A first and a second logic element within the dual path logic gate are functionally and possibly structurally equivalent, and are coupled to receive input signals spanning redundant input signal sets. A given logic structure within the first logic element may receive specified input signals within a particular input signal set, while an analogous logic structure within the second logic element may receive corresponding input signals within the counterpart input signal set. A radiation induced transient pulse that affects one input signal may affect an output signal asserted by one logic structure; however, since the transient pulse doesn't affect a corresponding input signal applied to the analogous logic structure, the dual path logic gate may output at least one correctly valued signal when a transient pulse occurs. The dual to single path converter is coupled to receive signals output by the dual path logic gate. In the event that a transient signal appears at an input of the dual to single path converter, a current path may be interrupted, and a correct output signal value is maintained as a result of stray capacitance present at an output node.

Logic architecture for single event upset immunity

A dual path ring oscillator core includes three dual path inverters, each having a first inverter and a second inverter. Within the first inverter, one transistor is coupled to a first output of a previous dual path inverter, while another transistor is coupled to a second output of the previous dual path inverter. Within the second inverter, one transistor is coupled to the second output of the previous dual path inverter, while another transistor is coupled to the previous dual path inverter's first output. A first and a final dual path inverter are analogously coupled. A transient pulse will not propagate through successive dual path inverter stages. A dual to single path converter is coupled to receive signals output by the final dual path inverter. If a transient signal appears at a dual to single path converter input, stray output node capacitance maintains a correct output signal value.

Ring oscillator providing single event transient immunity

A circuit includes a signal generator and a discriminator. The signal generator generates a plurality of reference signals where a majority of the reference signals have the same phase. The discriminator generates a regulated signal that has the same phase as the majority of the reference signals. Therefore, if an environmental disturbance such as a single-event transient (SET) shifts the phase or phases of a minority of the reference signals, the discriminator maintains the regulated signal at a stable frequency and phase by generating the regulated signal with reference to the undisturbed majority of the reference signals.

Redundant oscillator and method for generating a regulated signal

An oscillator includes an oscillator circuit that receives a control signal having a signal level. The oscillator circuit generates an oscillator signal having a frequency that is proportional to the signal level and that is within a frequency range. A compensation circuit stabilizes the oscillator circuit such that the frequency range includes first and second predetermined frequencies. Thus, such an oscillator can be used to generate an oscillator signal having a first frequency in one application and having a second frequency in another application. The compensation circuit stabilizes the frequency range of the oscillator signal so that it includes the first and second frequencies over broad ranges of operating conditions such as temperature and supply voltage and over broad ranges of component characteristics such as gate dielectric thickness.

Oscillator and method for generating a frequency within a stable frequency range

A transmitter directs a narrow RF ultrasonic beam through a body cavity to a receiver on the other side of the cavity. The beam is steered to be intercepted by audio signal sources in the body cavity, such as a fetal heart or multiple fetal hearts, which modulate the ultrasonic beam. The received parametric beam is demodulated and filtered to provide a relatively noise free audio reproduction of an audio signal source. In one embodiment, two transmitters are steered independently to direct respective beams to respective receivers to produce two signals and, thus, a binaural audio reproduction of an audio signal source. The audio reproduction is at a maximum when the two beams intersect at the audio signal source.

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Manassas, VA, United States of America

Kenneth R Knowles