H03M1/0836

SAR ADC AND SAMPLING METHOD BASED ON SINGLE-CHANNEL TIME-INTERLEAVED-SAMPLING

SAR ADC and sampling method based on single-channel TIS. The SAR ADC comprises: a capacitor array comprising a weight capacitor and a compensation capacitor, a first switch array, a second switch array, a channel switch group and a sampling switch; when in a sampling state: a lower plate of the weight capacitor is connected to an input voltage by means of the first switch array, and an upper plate of the capacitor array is connected to a common mode voltage by the sampling switch and the channel switch group; when in a successive approximation state: the lower plate of the weight capacitor is connected to a reference voltage by the second switch array. Input signals are sampled by using a unified to sampling switch, which solves the problem in the traditional technology that sampling moments are mismatched due to different sampling signals in each time-interleaved channel.

CALIBRATION SCHEME FOR A NON-LINEAR ADC

In described examples, an analog to digital converter (ADC), having an input operable to receive an analog signal and an output operable to output a digital representation of the analog signal, includes a voltage to delay (VD) block. The VD block is coupled to the input of the ADC and generates a delay signal responsive to a calibration signal. A backend ADC is coupled to the VD block, and receives the delay signal. The backend ADC having multiple stages including a first stage. A calibration engine is coupled to the multiple stages and the VD block. The calibration engine measures an error count of the first stage and stores a delay value of the first stage for which the error count is minimum.

High Gain Detector Techniques for High Bandwidth Low Noise Phase-Locked Loops
20220224343 · 2022-07-14 ·

In described examples, a phase locked loop (PLL) has a first phase detector cell (PD) that has a gain polarity. The first PD cell has a phase error output and inputs coupled to a reference frequency signal and a feedback signal. A second PD cell has an opposite gain polarity. The second PD cell has a phase error output and inputs coupled to the reference frequency signal and the feedback signal. A loop filter has a feedforward path and a (lossy) integrating path coupled to an output of the filter. The feedforward path has a third PD cell that has phase error output AC-coupled to the filter output. The integrating path includes an opamp that has an inverting input coupled to the first PD cell phase error output and a non-inverting input coupled to the second PD cell phase error output.

High Gain Detector Techniques for Low Bandwidth Low Noise Phase-Locked Loops
20220224348 · 2022-07-14 ·

In described examples, a feedback loop has phase detection (PD) circuitry that has a reference input to receive a reference frequency signal, a feedback input to receive a feedback signal, and phase difference outputs. A phase to digital converter (P2DC) includes a first phase to charge converter (PCC) that has a gain polarity and a first phase error output; a second PCC that has an opposite gain polarity and a second phase error output. A differential loop filter has an amplifier with an inverting input coupled to the first phase error output and a non-inverting input coupled to the second phase error output. An analog to digital converter (ADC) has an input coupled to an output of the differential loop filter. A feedback path is coupled to the output of the P2DC, with an output of the feedback path providing the feedback signal to the PD feedback input.

CALIBRATION SCHEME FOR FILLING LOOKUP TABLE IN AN ADC

In described examples, a circuit includes a calibration engine. The calibration engine generates multiple input codes. A digital to analog converter (DAC) is coupled to the calibration engine, and generates a first calibration signal in response to a first input code of the multiple input codes. An analog to digital converter (ADC) is coupled to the DAC, and generates multiple raw codes responsive to the first calibration signal. A storage circuit is coupled to the ADC and stores a first output code corresponding to the first input code. The first output code is obtained using the multiple raw codes generated by the ADC.

LOOKUP TABLE FOR NON-LINEAR SYSTEMS

In described examples, a circuit includes a multiplexer. The multiplexer receives an input voltage and a calibration signal. An analog-to-digital converter (ADC) is coupled to the multiplexer and generates an output code in response to the calibration signal. A storage circuit is coupled to the ADC and stores the input code representative of the calibration signal at an address corresponding to the output code. The stored input code includes an index value and a coarse value.

SEMICONDUCTOR CIRCUIT, RECEIVING DEVICE, AND MEMORY SYSTEM
20220301639 · 2022-09-22 · ·

According to the one embodiment, a semiconductor circuit includes: an analog-to-digital conversion circuit including a first analog-to-digital converter configured to sample at least one first sampling signal regarding an input signal based on a first clock, and a second analog-to-digital converter configured to sample at least one second sampling signal regarding the input signal based on a second clock shifted from the first clock by a first time; and a first calibration circuit configured to calibrate at least one timing of the first clock and the second clock based on a calculation result of a moving average of the first sampling signal and the second sampling signal.

Time interleaved analog-to-digital converter

A time interleaved analog-to-digital converter (TIADC) is provided. The TIADC converts an input signal into a digital output signal and includes N analog-to-digital converters (ADCs), a clock generation circuit, and a control circuit. The N ADCs receive the input signal and sample the input signal according to N sampling clocks to each generate a digital output code, N being an integer greater than or equal to 2. The clock generation circuit is configured to receive a working clock and a set of control values and to generate the N sampling clocks according to the set of control values and the working clock. The control circuit is configured to periodically generate the set of control values based on a pseudo random number and to output the digital output codes in turn as the digital output signal.

Time And Frequency Domain Signal Conditioning Device For Switching Noise Jitter (SNJ) Reduction, And Methods Of Making The Same
20220113352 · 2022-04-14 · ·

A time and frequency domain signal conditioning device including one or more signal terminals, one or more rails, and a passive signal conditioning means for reducing a switching noise jitter signature present in an output signal of a feedback control loop circuitry with a plurality of noise carrying jittering ramps is disclosed. The passive signal conditioning means including the rails is characterized by a set of specified characteristics to condition pre-existing noise amplitude and slopes of the output signal such that the conditioned output signal cooperates with the feedback control loop circuitry. As a consequence, the switching noise jitter signature which is produced by transient noise displacement or noise perturbation in the time domain when the output signal jitters can be reduced in the output of the feedback control loop circuitry.

Switched capacitor radio frequency digital power amplifier and radio frequency digital-to-analog converter

A switched capacitor digital power amplifier (DPA) or a digital-to-analog converter (DAC) is disclosed. The DPA/DAC includes a plurality of switched capacitor cells connected in parallel. Each switched capacitor cell includes a capacitor and a switch. The switch selectively drives the capacitor in response to an input digital codeword. The switched capacitor cells are divided into sub-arrays and a series capacitor is inserted in series between two adjacent sub-arrays of switched capacitor cells. All the sub-arrays of switched capacitor cells may be in a unary-coded structure. Alternatively, at least one of the sub-arrays may be in a C-2C structure and at least one another sub-array may be in a unary-coded structure. The switch in the switched capacitor cells is driven by a local oscillator signal, and a phase correction buffer may be added for adjusting a delay of the local oscillator signal supplied to sub-arrays of switched capacitor cells.