Patent application number | Description | Published |
20110175761 | DELTA SIGMA ANALOGUE TO DIGITAL CONVERTER - A delta sigma analogue to digital converter comprising: an integrator having first and second differential inputs for receiving an input analogue signal, the integrator having differential outputs; a quantiser having first and second differential inputs which receive signals output by the integrator, and an output which provides a digital output signal of the delta sigma analogue to digital converter, and a digital to analogue converter. The digital to analogue converter has an input which is connected to an output of the delta sigma analogue to digital converter, and first and second differential outputs. The first output of the digital to analogue converter is connected to the first input of the integrator such that if the second output of the digital to analogue converter is not connected to the second input of the integrator and the second input of the integrator is connected to a fixed reference voltage the delta sigma analogue to digital converter is able to operate in a single-ended mode. | 07-21-2011 |
20110260901 | Variable Gain Amplifier - A variable gain amplifier includes an integrator having an input, an output and a feedback loop connected between the input and output, a plurality of input chains connected in parallel between the amplifier input and the input of the integrator, each input chain including a resistor and a first switch and a plurality of second switches, each second switch connected between an intermediate node between the resistor and first switch of a respective input chain and the feedback loop of the integrator, wherein the resistance of the resistors in the input chains is scaled by a scaling factor with respect to one another and the on-resistances of the first and second switches connected to each intermediate node are scaled by the corresponding scaling factor. | 10-27-2011 |
20120194366 | MULTI-BIT DIGITAL TO ANALOGUE CONVERTER AND A DELTA-SIGMA ANALOGUE TO DIGITAL CONVERTER - The present invention relates to a multi-bit digital to analogue converter (DAC) and to a delta-sigma analogue to digital converter employing such a DAC. The DAC has a multi-bit input, a plurality of elements for processing an input signal received at the input and a selector for selecting, based on the input signal, one or more of the DAC elements to process the signal. The DAC has control means for controlling the selector such that if the input to the DAC is below a predetermined level for a predetermined period of time the selector is operative to select only a single one of the DAC elements to process the input signal. Also disclosed is a delta-sigma analogue to digital converter (ADC) employing such a DAC. | 08-02-2012 |
20120249235 | LOW DISTORTION AMPLIFER - A variable gain amplifier circuit ( | 10-04-2012 |
20130141176 | Highly Linear-Gain Oscillator - A variable frequency oscillator includes an inductance unit having a first inductance, a first variable capacitor coupled across the inductance unit, and a second variable capacitor coupled across a part of the inductance unit. The inductance of the part of the inductance unit coupled by the second variable capacitor is a proportion of the first inductance. | 06-06-2013 |
20140028374 | SPUR REDUCTION CIRCUIT - A circuit for modulating an input signal including a dither signal generator configured to generate a first dither signal having a maximum amplitude, a deamplifier configured to reduce the amplitude of said input signal so as to generate a deamplified input signal having a maximum amplitude that is comparable to the maximum amplitude of the dither signal, and a summer configured to sum the dither signal with the deamplified input signal. | 01-30-2014 |
20150084799 | MULTI-LEVEL QUANTIZERS AND ANALOGUE-TO-DIGITAL CONVERTERS - An analogue-to-digital converter employs one or more reference ladders for generating reference voltages with which to compare the analogue signal for quantization. Selected impedances of the reference ladder can be dynamically decoupled from the input signal in dependence on the value of the output signal in order to reduce headroom in the reference ladders, thus making possible accurate quantization in low-voltage applications. | 03-26-2015 |