H03M1/804

Adaptive settling time control for binary-weighted charge redistribution circuits
11681776 · 2023-06-20 · ·

A method and circuit for performing vector-matrix multiplication may include converting an input vector of binary-encoded values into analog signals using one-bit DACs, and sequentially performing a vector-matrix multiplication operation for each bit-order. The method may also include, for each sequentially performed operation, operating a switch that corresponds to a current bit-order. Operating the switch may cause a value corresponding to an output of the multiplier to be stored on a capacitor corresponding to the current bit-order. A time interval during which the switch is operated may be non-uniform with respect to time intervals for other switches, and the time interval may be based at least in part on a settling time of the capacitor. The method may also include performing a bit-order weighted summation of values stored on the plurality of capacitors to generate a result of the vector-matrix multiplication.

ANALOG READOUT PREPROCESSING CIRCUIT FOR CMOS IMAGE SENSOR AND CONTROL METHOD THEREOF
20170353685 · 2017-12-07 ·

The present disclosure provides an analog readout preprocessing circuit for a CMOS image sensor and a control method thereof. The analog readout preprocessing circuit comprises an extended count-type integration cycle-successive approximation hybrid analog-to-digital conversion capacitor network 1 configured to achieve readout and analog-to-digital conversion of signals output from the CMOS image sensor; an operational amplifier configured to utilize “virtual short” of two input terminals of the operational amplifier and the charge conservation principle, to achieve a function of extended count-type integration cycle-successive approximation hybrid analog-to-digital conversion, where the extended count-type integration can effectively reduce a thermal noise and a flicker noise within the image sensor; a comparator configured to compare voltages at two terminals to achieve a function of quantization of signals; and a control signal generator configured to provide control signals.

DIGITAL SLOPE ANALOG TO DIGITAL CONVERTER AND SIGNAL CONVERSION METHOD
20230188157 · 2023-06-15 ·

A digital slope analog to digital converter includes a charge injection digital to analog converter (DAC) circuit, a comparator circuit, a detector circuit, and a control logic circuitry. The charge injection DAC circuit respectively samples input signals via first and second capacitors and generates a first signal via the first capacitor and a second signal via the second capacitor. The comparator circuit compares the first signal with the second signal to generate decision signals. The detector circuit generates a flag signal according to the decision signals. The control logic circuitry generates an enable signal according to the flag signal and generates a digital output when the comparator circuit detects a crossing point of the first and second signals. The charge injection DAC circuit gradually adjusts charges stored in the first and/or the second capacitor according to the enable signal until the crossing point is detected.

OVERSAMPLING NOISE-SHAPING SUCCESSIVE APPROXIMATION ADC

A successive approximation Analogue to Digital Converter (ADC), comprising: a sample and hold device arranged to sample and hold an input signal at the beginning of a conversion cycle; a successive approximation register that sequentially builds up a digital output from its most significant bit to its least significant bit; a digital to analogue converter that outputs a signal based on the output of the successive approximation register; a comparator that compares the output of the digital to analogue converter with an output of the sample and hold device and supplies its output to the successive approximation register; and a residual signal storage device arranged to store the residual signal at the end of a conversion cycle; and wherein the successive approximation ADC is arranged to add the stored residual signal from the residual signal storage device to the input signal stored on the sample and hold device at the start of each conversion cycle. After each ADC full conversion by the SAR, the analogue conversion of the digital output is as close to the original input signal as the resolution will allow. However there remains the residual part of the input signal that is smaller than what can be represented by the least significant bit of the digital output of the SAR. In normal operation, successive outputs of a SAR for the same input will result in the same digital value output and the same residual. By storing the residual at the end of each conversion and adding the residual onto the input signal of the next conversion the residuals are accumulated over time so that they may affect the output digital value. After a number of conversions, the accumulated residuals add up to more than the value represented by the LSB of the register and the digital value will be one higher than if a conversion had been performed on the input signal alone. In this way, the residual signal affects the output value in time and thus can be taken into account by processing the digital output in the time domain.

CHARGE COMPENSATION CIRCUIT AND ANALOG-TO-DIGITAL CONVERTER WITH THE SAME
20170346498 · 2017-11-30 ·

A charge compensation circuit for use in an analog-to-digital converter (ADC) includes at least one capacitor and at least one logic circuit. A first terminal of the capacitor is coupled to a reference voltage of the analog-to-digital converter. The logic circuit is configured to adjust a voltage at a second terminal of the capacitor according to a control signal. The control signal is determined according to at least one output bit from the analog-to-digital converter.

Semiconductor device
11677412 · 2023-06-13 · ·

A semiconductor device performs sequential comparison of an analog input signal and a reference voltage to digitally convert the analog input signal. The semiconductor device includes an upper DAC generating a high-voltage region of the reference voltage based on a predetermined code, a lower DAC generating a low-voltage region of the reference voltage based on the code, and an injection DAC having the same configuration as that of the lower DAC and adjusting the low-voltage region of the reference voltage.

Converting large input analog signals in an analog-to-digital converter without input attenuation

In an example embodiment, an apparatus includes: a first sampling capacitor and a comparator to compare a sum voltage at a first input terminal to a voltage level at a second input terminal according to a thermometer cycle. The sum voltage is based at least in part on an analog input voltage and a divided reference voltage, where the analog input voltage and the reference voltage (V.sub.REF) are of a first voltage range and the divided reference voltage is according to ( ( 2 M - 1 ) V REF / 2 M ) ,
to enable the comparator to operate at a second voltage range, the second voltage range less than V REF / 2 M ,
and M is a number of bits of a digital output to be decided in the thermometer cycle and is greater than one.

INTEGRATED CIRCUIT

An integrated circuit includes an amplifier configured to amplify an analog signal, and an offset adjustment circuit that is provided in a stage prior to the amplifier and that is configured to adjust an offset amount of the analog signal to be amplified by the amplifier.

Sub-ranging SAR analog-to-digital converter with meta-stability detection and correction circuitry
09813073 · 2017-11-07 · ·

A sub-ranging SAR ADC has a coarse flash ADC that generates bit values corresponding to MSBs of the digital output value, and a fine SAR ADC that generates bit values corresponding to LSBs of the digital output value. The fine ADC generates successive analog approximation signals for the analog input signal. Meta-stability (MTS) detection circuitry detects a coarse-ADC MTS condition in the coarse ADC if a magnitude of a difference between a current approximation signal and a previous approximation signal is greater than a specified threshold level. A controller controls operations of the sub-ranging ADC to correct for a detected coarse-ADC MTS condition. The MTS detection circuitry includes a positive MTS detector that detects a positive coarse-ADC MTS condition in the coarse ADC and a negative MTS detector that detects a negative coarse-ADC MTS condition in the coarse ADC.

Method and apparatus for use in digitally tuning a capacitor in an integrated circuit device
11258440 · 2022-02-22 · ·

A method and apparatus for use in a digitally tuning a capacitor in an integrated circuit device is described. A Digitally Tuned Capacitor DTC is described which facilitates digitally controlling capacitance applied between a first and second terminal. In some embodiments, the first terminal comprises an RF+ terminal and the second terminal comprises an RF− terminal. In accordance with some embodiments, the DTCs comprise a plurality of sub-circuits ordered in significance from least significant bit (LSB) to most significant bit (MSB) sub-circuits, wherein the plurality of significant bit sub-circuits are coupled together in parallel, and wherein each sub-circuit has a first node coupled to the first RF terminal, and a second node coupled to the second RF terminal. The DTCs further include an input means for receiving a digital control word, wherein the digital control word comprises bits that are similarly ordered in significance from an LSB to an MSB.