Patent application number | Description | Published |
20090003628 | DRIVERS AND METHODS FOR DRIVING A LOAD - Embodiments of the present invention provide methods and devices for controlling a command signal applied to a load. In embodiments of the invention, current through and voltage across a load are determined and the values of both are used to generate a hybrid control signal. For example, in some embodiments the hybrid control signal is generated by taking a weighted summation of the current and voltage control signals. In other embodiments, a percentage of the difference between the current and voltage control signals is added to one of the current or voltage control signals to generate the hybrid control signal. In one embodiment, a potentiometer is used to generate the hybrid control signal. | 01-01-2009 |
20090121703 | LOAD CURRENT SENSING TECHNIQUE - Methods and apparatus regulate the output of a switching device to a voltage near that of saturation. In the preferred embodiment, this is accomplished for a small period of time during activation before and/or after device saturation. The switching device drive requirement is then measured to attain the regulated voltage. Measurement of the drive requirement during the small period of time correlates to switching driver current, being reliant on the finite gain of the switching device. | 05-14-2009 |
20100001794 | METHOD AND SYSTEM FOR INCREASING SAMPLING FREQUENCY FOR SWITCHING AMPLIFIERS - The present invention is directed toward providing a system and method of reducing RF interference in switching amplifiers without degrading performance. In one embodiment, the sampling rate of coarse high voltage modulated pulsewidths are increased relative to the sampling rate of fine lower voltage modulated pulsewidths. This increase in the sampling rate of coarse high voltage modulated pulsewidths results in a reduction in EMI. | 01-07-2010 |
20100066447 | FILTER COMPENSATION FOR SWITCHING AMPLIFIERS - Embodiments of the present invention provide methods and systems for limiting bipolar current flow in a switching amplifier. Embodiments of the present invention are directed to a multi-referenced switching amplifier. In some embodiment, the switching amplifier is a dual referenced switching amplifier comprising a regulator between the two references, where the first reference provides coarse modulation to a load and the second reference provides fine modulation to the load. The dual referenced switching amplifiers comprise the output filters made up of an inductor and a capacitor. In some embodiments, fine modulation is not applied to the load, thus limiting bipolar current flow induced by the filter inductors. | 03-18-2010 |
20100102881 | SAMPLING FREQUENCY REDUCTION FOR SWITCHING AMPLIFIERS - The present invention is directed toward providing a system and method of reducing RF interference in switching amplifiers without degrading performance. In one embodiment, the sampling rate of coarse high voltage modulated pulsewidths are decreased relative to the sampling rate of fine lower voltage modulated pulsewidths. This reduction in the sampling rate of coarse high voltage modulated pulsewidths results in a reduction in EMI. In addition, the higher sampling rate of the fine lower voltage modulated pulsewidths mitigates the distortion caused by the reduced sampling rate of the coarse pulsewidths. | 04-29-2010 |
20100182084 | LOW RF INTERFERENCE SWITCHING AMPLIFIER AND METHOD - A switching amplifier includes first and second output terminals that may be connected to a load. A pulse-width modulator receiving an input signal to obtain respective positive and negative values of the input signal. The modulator is connected to first and second switching circuits. The first switching circuit applies a plurality of pulses to the first output terminal that, in response to the positive samples, have a constant frequency and are pulse-width modulated, and, in response to the negative samples, have a varying frequency and a constant width. Similarly, the second switching circuit applies a plurality of pulses to the second output terminal that, in response to the negative samples, have a constant frequency and are pulse-width modulated, and, in response to the positive samples, have a varying frequency and a constant width. The varying phase of the constant width pulses disperses RF interference across a wider spectrum. | 07-22-2010 |
20110210790 | FILTER COMPENSATION FOR SWITCHING AMPLIFIERS - Embodiments of the present invention provide methods and systems for limiting bipolar current flow in a switching amplifier. Embodiments of the present invention are directed to a multi-referenced switching amplifier. In some embodiment, the switching amplifier is a dual referenced switching amplifier comprising a regulator between the two references, where the first reference provides coarse modulation to a load and the second reference provides fine modulation to the load. The dual referenced switching amplifiers comprise the output filters made up of an inductor and a capacitor. In some embodiments, fine modulation is not applied to the load, thus limiting bipolar current flow induced by the filter inductors. | 09-01-2011 |
Patent application number | Description | Published |
20100262042 | ACOUSTIC MYOGRAPHY SYSTEM AND METHODS - Acoustic impulses from a muscle are converted into an electrical signal with a transducer such as a piezo film microphone, and analog or digital signal processing circuitry determines the density of self-similar spectral components of the signal and generating an output signal representative of the contractile force of the muscle based upon the density of the self-similar spectral components. The circuitry is used to determine self-similar spectral components of the signal and the density of those components, and the density is used to provide an output signal filtering. Different embodiments use combinations of filtering, Fourier analysis and correlation or auto-correlation. The self-similar spectral components may be pre-determined or determined through signal processing. The output signal may be used to calculate muscle contractile force, fatigue or other muscle conditions. | 10-14-2010 |
20100268080 | APPARATUS AND TECHNIQUE TO INSPECT MUSCLE FUNCTION - A system and method for extracting functional and/or diagnostic information from acoustic emissions indicative of muscle activity. Time domain signals are transformed into the frequency domain while preserving temporal content, isolating and preserving the sign of changes of frequencies so obtained in a preserved temporal context, and presenting the frequency derivatives so obtained in the time domain, correlated with other sound features or aspects. | 10-21-2010 |
20130246036 | ORTHOTIC SUPPORT AND STIMULUS SYSTEMS AND METHODS - An embodiment of the invention includes (a) modeling a first internal force applied to a model of a user's joint based on a first external force externally applied to the joint at a first position; (b) modeling a second internal force applied to the model based on a second external force externally applied to the joint at a second position unequal to the first position; (c) comparing the first and second modeled internal forces; and (d) simulating the user based on the comparison. Other embodiments are described herein. | 09-19-2013 |
20140148873 | JOINT REHABILITATION APPARATUS AND TECHNIQUE - An embodiment includes simultaneously supplying direct current (DC) energy to recondition cartilage of a knee joint while simultaneously protecting that cartilage by supplying alternating current (AC) energy to stimulate muscle tissue contralateral to the cartilage to at least partially decompress the cartilage and at least partially support the joint. Other embodiments are described herein. | 05-29-2014 |
Patent application number | Description | Published |
20100327845 | Apparatus and Technique to Drive a Variable Load - The primary of a transformer is driven at low voltages to provide high-voltage dynamic drive from the secondary to a load. A high-current source is placed in series with both the transformer secondary and load. At least secondary inductance of the transformer, hence impedance, is controlled through core saturation to transition secondary output to the load between high-voltage dynamic drive inductively coupled from the primary, and high-current drive serially connected through the secondary. Switching between high voltage and high current output is accomplished through the transformer; no additional switching devices need exist in the high-voltage path. Broad voltage and current capabilities of the configuration inexpensively improve transient drive of highly reactive loads. | 12-30-2010 |
20110015696 | Adaptive Muscle Stimulation Apparatus and Methods - A portable device, with requisite method, is used to support a compromised joint, such as by arthritis, through dynamic stimulation of the surrounding musculature. Direct feedback, preferably from the patient wearing the device, is used during problematic joint operation to qualify dynamic measured or calculated spacial or physical conditions of the compromised joint for use as state definitions. Approximation of these state definitions by subsequent spacial or physical conditions of the compromised joint evokes variable stimulation of the surrounding musculature. State definitions so qualified, as well as control of stimulation output, may include magnitude and/or vector of joint force, facilitating predictable benefit from the device beyond that available through positional control. | 01-20-2011 |
20110015922 | Speech Intelligibility Improvement Method and Apparatus - Prevalence detection is advantageously applied to the result of specific spectral discrimination to adaptively determine prevalent frequencies existing within an audio signal containing speech. Prevalent frequencies in this audio signal so isolated are attenuated in a highly selective manner, thus reducing the masking potential of pervasive resonances and obfuscative energy within the speech itself over low energy language-imparting speech elements. | 01-20-2011 |
20110118853 | Prosthetic Socket Stabilization Apparatus and Technique - A portable device, with method, advantageously applies dynamic stimulation of enclosed muscle tissue to stabilize a prosthetic socket on a residual limb. Dynamic stimulation is in response to physical conditions such as prosthesis motion, position and/or internal pressures. Tissue volume contained within the socket may be stabilized by varying average stimulation levels in response to internal socket pressure. | 05-19-2011 |
20120022877 | Dynamic Range Improvement Technique - Apparatus and methods are disclosed for detecting and progressively attenuating specific frequencies prevalent in an audio signal. In contrast to conventional wide-band enhancement techniques over long time frames, narrow bandwidths and short attenuation times employed are commensurate with resonances and timing typical of speech. Apparent dynamic range is therefore increased through attenuation of longer-duration elements with declining informational contribution. | 01-26-2012 |
20130253607 | Adaptive Muscle Stimulation Technique - An embodiment of the invention resides in the apparatus and technique of dynamically measuring and storing a biological condition or disposition during the time that one set of conditions are imposed on a joint or body area and applying closed-loop therapeutic action so as to re-achieve that same biological condition or disposition during a subsequent time that another different set of conditions are imposed. Furthermore, dynamic potentials surrounding said joint or body area may be created, bolstered, and/or modulated through aspects of stimulation applied which are independent of those aspects utilized to counteract force incident on the joint or body area. Other embodiments are described herein. | 09-26-2013 |