A system may comprise a high-pass filter having an input for receiving an input signal, an output for generating an output signal, a capacitor coupled between the input and the output, a switched-capacitor resistor coupled between the output and a reference voltage, and control circuitry configured to control the reference voltage to cancel current leakage into a circuit coupled to the output. The input, the output, the capacitor, and the switched-capacitor resistor may be arranged to generate the output signal as a high-pass filtered version of the input signal and the high-pass filter may be configured to operate in a plurality of modes comprising at least a high-impedance mode and a low-impedance mode in which the resistance of the switched-capacitor resistor is significantly smaller than the resistance when in the high-impedance mode. A system may include a plurality of processing paths having a first path configured to generate a first digital signal based on an analog input signal and a second path configured to generate a second digital signal based on the analog input signal, the second path having a high-pass filter for filtering the analog input signal prior to the analog input signal being processed by the remainder of the second path, and the high-pass filter having a corner frequency. Control circuitry may be configured to determine frequency-dependent weighted proportions of the first and second digital signals to be combined into an output digital signal based on a characteristic of the analog input signal. Frequency-dependent weighted proportions may be such that the digital output signal includes spectral content of the first digital signal below the corner frequency to account for spectral content of the second digital signal below the corner frequency being filtered. A system may include an input for receiving an input signal, an output for generating an output signal, a capacitor coupled between the input and the output, a variable resistor coupled to the output and having a plurality of modes including a first mode in which the variable resistor has a first resistance and a second mode in which the variable resistor has a second resistance, and control circuitry configured to determine a difference between the input signal and the output signal and switch between modes of the plurality of modes when the difference is less than a predetermined threshold.

A signal processing apparatus, a signal processing system and a signal processing method are provided. The signal processing apparatus includes at least one analog channel and an analog-to-digital conversion unit. Each of the at least one analog channel is configured to, in response to receiving a first analog signal inputted from outside, condition the first analog signal to generate a second analog signal, and send the second analog signal to the analog-to-digital conversion unit. The analog-to-digital conversion unit is configured to convert the second analog signal sent from any of the at least one analog channel into a digital signal.

The disclosure provides a circuit. The circuit includes a zone detection block that generates a control signal in response to an input signal. An amplifier generates an amplified signal in response to the input signal and the control signal. An analog to digital converter (ADC) is coupled to the amplifier and samples the amplified signal to generate a digital signal. A digital corrector is coupled to the zone detection block and the ADC, and transforms the digital signal to generate a rectified signal based on the control signal and an error signal. An error estimator is coupled to the zone detection block and receives the rectified signal as a feedback. The error estimator generates the error signal in response to the control signal and the rectified signal.

Certain aspects are directed to an apparatus configured for wireless communication. The apparatus may include a memory comprising instructions, and one or more processors configured to execute the instructions. In some examples, the one or more processors are configured to cause the apparatus to obtain a sample of an analog signal. In some examples, the one or more processors are configured to cause the apparatus to output the sample to an analog-to-digital converter (ADC) via one of at least a first path or a second path based at least in part on whether the sample satisfies a first threshold condition or a second threshold condition.

According to certain aspects, a predictive tracking scheme is provided for sampling inductor currents in a digital PWM controller used for high-bandwidth voltage regulation. In one or more embodiments, the predicted current derived from the PWM waveform is fed forward to the current sense ADC in order to reduce the required conversion range. These and other embodiments only need to convert a few of the LSB of the ADC in order to correct the largest error expected in the synthesizer.

A multi-input analog-to-digital converter (ADC), i.e., a single ADC, can receive multiple analog input signals and generate multiple digital outputs. To combine multiple analog input signals into a single multi-input ADC, the multi-input ADC would typically include multiple track and hold (T/H) circuits and an adder, which can consume a significant amount of power and incur large cost overhead. An improved approach is to combine multiple inputs through a unique T/H circuit in the front-end of the ADC. The multiple analog input signals can be aggregated using code sequences, without requiring a significant amount of external circuits.

Techniques are provided for compensating gain of a combined amplifier and analog-to-digital converter (ADC) circuit, for example, due to additional filtering added to an input of the circuit. In an example, an integrated circuit including an amplifier and ADC can include an amplifier circuit configured to receive an input signal and to amplify the input signal based on an input resistance and a feedback resistance, and to provide an amplified representation of the input signal, and an ADC circuit configured to receive an output of the amplifier, to determine a digital coefficient associated with an additional input resistance coupled to the amplifier, and to provide a compensated digital representation of the amplified representation of the input signal using the digital compensation coefficient.

A radio-frequency signal preconditioning method includes: receiving, at a radio-frequency signal preconditioning apparatus from an antenna, a radio-frequency signal; selectively providing, at the radio-frequency signal preconditioning apparatus, any of a plurality of gains to the radio-frequency signal to produce an output signal, the plurality of gains spanning a first range; and providing, from the radio-frequency signal preconditioning apparatus, the output signal to a conversion circuit configured to convert the output signal from an analog signal at a radio frequency to a digital signal at a baseband frequency, the conversion circuit having a dynamic range spanning a second range that is smaller than the first range.

A system includes an analog-to-digital converter receiving input signals. One particular input signal has a particular analog value, and the analog-to-digital converter uses a fixed reference to convert the particular analog value to a particular digital value. The analog-to-digital converter uses the particular analog value as a reference for converting the analog values of the remaining input signals.

A signal processing apparatus, a signal processing system and a signal processing method are provided. The signal processing apparatus includes at least one analog channel and an analog-to-digital conversion unit. Each of the at least one analog channel is configured to, in response to receiving a first analog signal inputted from outside, condition the first analog signal to generate a second analog signal, and send the second analog signal to the analog-to-digital conversion unit. The analog-to-digital conversion unit is configured to convert the second analog signal sent from any of the at least one analog channel into a digital signal.