Abstract:
A filter provides high-pass coupling between circuits. The filter includes charge storage elements and switch elements coupling the charge storage elements. A controller is coupled to the switch elements for sequencing configurations of the switch elements in phases for each of a succession of sample periods to perform a time sampled continuous value signal processing of the input signal to form the processed signal. The sequenced configurations include a configuration in which a charge representing a value of the input signal is stored on a multiple of the charge storage elements, a configuration in which charge storage elements are coupled with the switch elements, and a set of one or more configurations that implement a scaling of a charge on one of the charge storage elements to be on one or more of the charge storage elements.
Abstract:
An approach to time domain filtering uses a passive charge sharing approach to implement an infinite impulse response filter. Delayed samples of an input signal are stored as charges on capacitors of a first array of capacitors, and delayed samples of the output signal are stored as charges on capacitors of a second array of capacitors. Outputs are determined by passively coupling capacitors of the first and second arrays to one another, and determining the output according to a total charge on the coupled capacitors. In some examples, a gain is applied to the total charge prior to storing the output on the second array of capacitors. In some examples, a charge scaling circuit is applied to the charges stored on the arrays prior to coupling capacitors to form the output.
Abstract:
A storage device includes a storage array having a group of storage elements. Each storage element can written to a discrete set of physical states. A read circuit selects one or more storage elements and generates, for each selected storage element, an analog signal representative of the physical state of the selected storage element. A signal processing circuit processes the analog signal to generate a plurality of outputs, with each output representing a degree of an association of the selected storage element with a different subset of one or more of the discrete set of physical states.
Abstract:
A low voltage driver for a higher voltage LCD includes a plurality of LCD drive bias voltage input-terminals; an LCD drive voltage output terminal; an input transistor switching circuit having at least one switch for each LCD drive bias voltage for selecting one of the bias voltages; an output transistor switching circuit, responsive to the input transistor switching circuit, for applying the selected one of the bias voltages to the LCD drive voltage output terminal, the transistors of the switching circuits having a predetermined breakdown voltage; a level shifter for providing switching voltages counterpart to the plurality of bias voltages; a logic circuit for enabling the first transistor switching circuit to select a one of the bias voltages and applying a set of counterpart switching voltages to the input and output transistor switching circuits for connecting the selected one of the bias voltages to the output terminal and applying a set of switching voltages to the input and output switching circuits which limit the voltage across the transistor junctions in the switching circuit to less than the predetermined breakdown voltage.
Abstract:
An analog-to-digital metering circuit includes a first programmable gain amplifier to amplify a first voltage signal from a first channel before being received by a first analog-to-digital converter that converts the amplified first voltage signal to a first digital signal. A second programmable gain amplifier amplifies a second voltage signal from a second channel and feds the amplified signal to a second analog-to-digital converter that converts the amplified second voltage signal to a second digital signal. A first lowpass filter circuit receives the first and second digital signals, to generate therefrom, a multi-bit analog-to-digital value. A direct digital synthesizer generates a digital signal representing a predetermined waveform that is fed to a digital-to-analog converter. The second voltage signal and the digital signal representing the predetermined waveform are multiplied together to generate a digital value. Phase shifting circuitry provides a signal representing a 90-degree phase shift of the digital value and a signal representing a 0-degree phase shift of the digital value. RMS circuitry converts the 0-degree phase digital signal into an In-Phase signal and the 90-degree phase digital signal into a Quadrature signal.
Abstract:
A power metering system including a first modulator receiving a first analog voltage associated with a current and outputting a first digitized signal. A second modulator receives a second analog voltage and outputs a second digitized signal. A first lowpass filter filters out high frequency noise associated with the first signal and decimates the frequency of the first digitized signal. The first lowpass filter outputs a first filtered signal. An interpolator performs up sampling of the signal associated with the first filtered signal. The interpolator outputs a first up sampled signal. An integrator integrates the first up sampled signal. The integrator outputs an integrated signal. A first multiplier multiplies the second digitized signal and integrated signal, and outputs a multiplied signal. The multiplied signal being used to measure power.
Abstract:
A sampling capacitor interface circuit for storing charge on a sampling capacitor related to a sample of an input signal voltage during a charging phase and to transfer the stored charge to an output during a charge transfer phase, such input signal having bipolar voltages within a range above and below an input signal common mode voltage. The interface circuit includes a transistor having: an input electrode fed by the input signal; an output electrode coupled to the sampling capacitor; and, a control electrode. A controller is provided for producing a control signal having a first voltage during the charging phase and a second voltage during the charge transfer phase, such voltages being a unipolar voltage referenced to the input signal common mode voltage. A bias circuit is coupled to the input signal and has a level shifting capacitor coupled between the controller and the control electrode for storing a voltage during the charge transfer phase and for shifting the first voltage by the stored voltage during the charging phase to provide a voltage at the control electrode with a level sufficiently below the input signal common mode voltage to bias the transistor to a conducting condition during the charging phase over the range of input signal voltages.
Abstract:
Microphone stages in a microphone array may be coupled together in a daisy chain. Each stage may include a microphone, an analog to digital converter, a decimation unit, a receiver, an adder, and a transmitter. The converter may convert analog audio microphone signals into digital codes that may be decimated. The adder may add decimated digital codes in each stage to a cumulative sum of decimated digital codes from prior stages. This new sum may be transmitted to the next microphone stage, where the adder may add the decimated digital codes from that stage to the cumulative sum. A serial interface may be used to connect the transmitters and receivers of each of the stages. The serial interface may be used to transmit the cumulative sum of decimated digital codes between the stages. The serial interface may also be used to transmit configuration data between the stages.
Abstract:
Some general aspects of the invention relate to a circuit and to a method for analog computation, for example, using switched capacitor integrated circuits. In some examples, a circuit includes a first group of capacitors and a second group of capacitors that may store charges during circuit operation. The first and/or the second group of capacitors may include multiple disjoint subsets of capacitors. An input circuit is provided for receiving a set of input signals and for inducing a charge on each of some or all capacitors in the first group of capacitors according to a corresponding input signal. Switches, for example, transistors controlled by a sequence of clock signals, are used to couple different sets of capacitors. Different configurations of the switches are used to form different sets of the capacitors among which charge can redistribute.
Abstract:
The present invention is based on the discovery that overexpression of ΔFosB leads to bone formation and that ΔFosB expression inhibits adipogenesis. The present invention provides methods of identifying agents that modulate bone formation and adipogenesis. Moreover, the present invention provides methods for identifying genes that are modulated by ΔFosB and that modulates ΔFosB, osteogenesis, and adipogenesis.