Patent application number | Description | Published |
20090257558 | NOISE LIMITATION OF A SIGNAL DEPENDENT MULTIBIT DIGITAL TO ANALOG SIGNAL CONVERSION - Several methods and a system of noise limitation of a signal dependent multibit digital to analog signal conversion are disclosed. An exemplary embodiment provides a method that includes receiving an output of a multibit analog to digital circuit of a continuous time sigma delta converter. The method further includes limiting a noise generation by adaptively selecting a digital to analog converter element out of a plurality of digital to analog converter elements in accordance with an input signal magnitude. In addition, the method includes implementing a selected digital to analog converter element to generate an analog signal. | 10-15-2009 |
20100052741 | DUAL INTEGRATOR CIRCUIT FOR ANALOG FRONT END (AFE) - A circuit includes a generating circuit that generates a current signal in response to an input signal, a first one of a plurality of integrators that generates a voltage signal from the current signal, a comparator that is responsive to the voltage signal to compare the voltage signal with a predefined voltage, a switching circuit that reconfigures a first capacitor and a second capacitor connected to the first one of the plurality of integrators to discharge the first capacitor and to enable the second capacitor to generate the voltage signal in response to the current signal, and an analog-to-digital converter to generate an output when a predefined time interval has elapsed. The output is obtained by adding a first charge value corresponding to a count of number of times the voltage signal reaches the predefined voltage in the predefined time interval and a second charge value from the analog-to-digital converter. | 03-04-2010 |
20100080083 | Time-Dependant Gain Control For An Amplifier Used In Receiving Echoes - An amplifier circuit to amplify a sequence of echoes and to generate a corresponding sequence of amplified signals. In an embodiment, the amplifier includes an operational amplifier, with variable input and feedback resistances such that the ratio of the two resistances can be controlled. A gain control block controls the ratio in a time dependent manner to obtain desired gain factors for each of the echoes. The gain factors can be pre-computed such that all the echoes are gained to the same level in case of an ultra-sound system. | 04-01-2010 |
20130039151 | CANCELLATION OF PRODUCTS GENERATED BY HARMONICS OF A SQUARE WAVE USED IN SQUARE-WAVE MIXING - A mixer circuit includes three square wave mixers and a combiner. A first square wave mixer in the circuit multiplies an input signal with a first square wave. A second square wave mixer and a third square wave mixer in the circuit each multiplies the input signal with a second square wave and a third square wave respectively. The second and third square waves have a same frequency as the first square wave, but phases that respectively lead and lag the phase of the first square wave by a first value. The combiner adds the outputs of the mixers. A low-pass filter external to the mixer circuit filters the sum generated by the combiner to generate a filtered output. In an embodiment, the first value equals forty five degrees, and the filtered output is rendered free of products generated by third and fifth harmonics of the first square wave square. | 02-14-2013 |
20130258812 | ULTRASONIC RECEIVER FRONT-END - In certain embodiments, systems for receiving one or more echoes are provided. The system comprises a first attenuator, a first amplifier, and a second attenuator. The first attenuator is configured to receive the one or more echo signals, and generate a corresponding set of first attenuated echo signals, respectively, based on a number of signal strengths of the one or more echo signals. The first amplifier is configured to receive and amplify the set of first attenuated echo signals to thereby generate a set of first amplified echo signals corresponding to the one or more first attenuated echo signals, respectively. The second attenuator is configured to receive the set of first amplified echo signals and generate a set of second attenuated echo signals corresponding to the set of first amplified echo signals, respectively, based on a number of signal strengths of the set of first amplified echo signals, respectively. | 10-03-2013 |
20150116695 | LIGHT RADAR SIGNAL PROCESSING APPARATUS, SYSTEMS AND METHODS - Samples of a light radar (“LIDAR”) return signal are stored in an analog circular buffer following the transmission of a LIDAR pulse. Sampling continues for a fixed period of time or number of samples during a post-trigger sampling period after the occurrence of a trigger signal from a trigger circuit. The trigger circuit indicates the receipt of a return pulse associated with a target object based upon one or more return signal characteristics. Following the post-trigger sampling period, the stored analog samples are sequentially read out and converted to digital sample values. The digital sample values may be analyzed in a digital processor to further confirm the validity of the returned LIDAR pulse, to determine a time of arrival of the LIDAR pulse, and to calculate a distance to the target object. Some versions include multiple circular buffers and capture clocks, enabling the capture of samples from multiple return pulses. | 04-30-2015 |
20150280662 | TIME GAIN COMPENSATION CIRCUIT IN AN ULTRASOUND RECEIVER - The disclosure provides a time gain compensation (TGC) circuit. The TGC circuit includes an impedance network. A differential amplifier is coupled to the impedance network. The differential amplifier includes a first input port, a second input port, a first output port and a second output port. A first feedback resistor is coupled between the first input port and the first output port. A second feedback resistor is coupled between the second input port and the second output port. The impedance network provides a fixed impedance to the differential amplifier when a gain of the TGC circuit is changed from a maximum value to a minimum value. | 10-01-2015 |
Patent application number | Description | Published |
20110012764 | MULTIBIT RECYCLIC PIPELINED ADC ARCHITECTURE - An apparatus is provided. The apparatus comprises a sample switch, a sampling capacitor, an amplifier, feedback branches, a second hold switch, an N-bit converter pair, a third hold switch, and an M-bit converter pair. The sample receives an input signal and is actuated by a sample signal. The sampling capacitor is coupled to the sample switch. The amplifier has a first input terminal that is coupled to the sampling capacitor. The feedback branches are coupled between the output terminal of the amplifier and the first input terminal of the amplifier, with each feedback branch including a feedback capacitor, and a first hold switch that is coupled to the feedback capacitor. The second hold switch is coupled to the sampling switch. The N-bit converter pair is coupled to the sampling switch and to the second hold switch. The third hold switch is coupled to at least one of the feedback branches, and the M-bit converter pair is coupled to the output terminal of the amplifier and to the third hold switch. | 01-20-2011 |
20110128172 | LOW POWER CONVERT AND SHUTDOWN SAR ADC ARCHITECTURE - With Successive Approximation Register (SAR) analog-to-digital converters (ADCs), there are several different architectures. One of these architectures is a “convert and shut down” architecture, where an internal amplifier is powered down during the sampling phase to reduce power consumption. This powering down comes at a price in that a portion of the convert phase is lost waiting for the amplifier to be powered back up. Here, an apparatus is provided that makes use of the entire convert phase by coarsely resolving a few bits during the period in which the amplifier is powering up to have an increased resolution over conventional SAR ADCs with “convert and shut down” architecture, while maintaining low power consumption. | 06-02-2011 |
Patent application number | Description | Published |
20130021185 | Low Noise Front End For Pulsed Input System - Embodiments of the invention provide a pulsed signal detection system with reduced noise bandwidth in the frontend. Analog to digital conversion speed is decoupled from the pulsed duty cycle timing. This in turn reduces the power consumption of the ADC and the front end while providing a high dynamic range. The ADC may be a continuous time sigma delta converter to reduce the drive requirements of the front end. | 01-24-2013 |
20150054560 | DC Offset Correction with Low Frequency Signal Support Circuits and Methods - DC offset correction is provided with low frequency support. A first input terminal for receiving an input signal is selectively coupled to a resistance and a capacitor that are series coupled between the first input terminal and a corresponding output terminal. In a calibration phase, the series resistance is coupled between the input terminal and the capacitor and an average voltage level of the input is stored on capacitor. In a signal processing phase, the charged capacitor is coupled in series between the input terminal and the output terminal while the resistance is bypassed. The output signal obtained contains the high and low frequency components of the input signal, while the DC offset in the input signal is removed from the output signal. A differential circuit and methods are disclosed. Additional embodiments are disclosed. | 02-26-2015 |
20150256151 | METHOD AND APPARATUS TO REDUCE NOISE IN CT DATA ACQUISITION SYSTEMS - The disclosure provides a circuit that includes an integrator that generates an integrated signal in response to a current signal. A comparator is coupled to the integrator and receives the integrated signal and a primary reference voltage signal. The comparator generates a feedback signal. A switched capacitor network is coupled across the integrator. The feedback signal activates the switched capacitor network. | 09-10-2015 |
20150260571 | TIME-OF-FLIGHT (TOF) RECEIVER WITH HIGH DYNAMIC RANGE - The disclosure provides a receiver with high dynamic range. The receiver includes a photodiode that generates a current signal. A coupling capacitor is coupled to the photodiode, and generates a modulation signal in response to the current signal received from the photodiode. A sigma delta analog to digital converter (ADC) is coupled to the coupling capacitor, and generates a digital data in response to the modulation signal. A digital mixer is coupled to the sigma delta ADC, and generates an in-phase component and a quadrature component corresponding to the digital data. A processor is coupled to the digital mixer, and processes the in-phase component and the quadrature component corresponding to the digital data. | 09-17-2015 |
20150293045 | MEASURING ELECTRODE IMPEDANCE IN AN IMPEDANCE MEASUREMENT CIRCUIT - The disclosure provides a circuit for impedance measurement. The circuit includes an excitation source coupled between a first set of input switches. An impedance network is coupled between the first set of input switches and a first set of output switches. The impedance network includes a body impedance and a plurality of electrode impedances. A sense circuit is coupled to the first set of output switches. The sense circuit measures the body impedance and at least one electrode impedance of the plurality of electrode impedances. | 10-15-2015 |
20150305648 | IMPEDANCE MEASUREMENT CIRCUIT - The disclosure provides a circuit for impedance measurement. The circuit includes an excitation source that generates an excitation signal. A switched resistor network is coupled to the excitation source, and generates an output signal in response to the excitation signal. A sense circuit is coupled to the switched resistor network, and generates a sense signal in response to the output signal. A comparator is coupled to the sense circuit, and generates a clock signal in response to the sense signal. A mixer is coupled to the sense circuit, and multiplies the sense signal and the clock signal to generate a rectified signal. A low pass filter is coupled to the mixer and filters the rectified signal to generate an averaged signal. A processor is coupled to the low pass filter and measures a body impedance from the averaged signal. | 10-29-2015 |