An exemplary quantizer includes a multi-bit analog-to-digital converter (ADC) and a first digital-to-analog converter (DAC) feedback circuit. The multi-bit ADC has an internal DAC associated with comparison of each sampled analog input of the multi-bit ADC. The multi-bit ADC converts a currently-sampled analog input into a first digital output. A first noise-shaped truncation output is derived from the first digital output. The first DAC feedback circuit transfers a first truncation residue associated with the first noise-shaped truncation output to the internal DAC. The transferred first truncation residue is reflected in comparison of a later-sampled analog input of the multi-bit ADC via the internal DAC.

A device (e.g., SAR ADC device) include a DAC circuit and generates a digital output based on logic circuitry that includes SAR logic. Additional logic circuitry includes delta modulation circuitry and dynamic element matching circuitry. The delta modulation circuitry provides several digital outputs of the SAR DAC, while the dynamic element matching circuitry selects a different set of capacitors from the DAC circuit. Each cycle is added together and averaged, and then added to the digital output from the SAR logic.

The invention provides a system for conversion between analog domain and digital domain with mismatch error shaping, including a DAC, a first injection circuit coupled to the DAC, and a second injection circuit coupled to the DAC. The DAC generates a first analog value in response to a first digital value, and generates a second analog value in response to a second digital value. The first injection circuit enables an analog injection value to be injected to the second analog value when the DAC generates the second analog value, wherein the analog injection value is converted from a digital injection value formed by a subset of bits of the first digital value. The second injection circuit injects the digital injection value to the second digital value, or combines the digital injection value and a related value obtained according to the second analog value.

Noise and distortion reduction in a signal processed through analog circuitry includes providing noise reduction circuitry to reduce signal noise generated by at least one analog circuit element. The noise reduction circuitry is adaptively configured to adjust a rate to apply noise reduction to the signal without introducing unwanted distortion. Distortion reduction circuitry is adaptively configured to adjust a rate to apply distortion reduction to the signal without introducing unwanted noise. The signal is processed through the analog circuitry using the adaptively configured noise reduction circuitry and adaptively configured distortion reduction circuitry to reduce both noise and distortion in the signal.

The invention provides a system for conversion between analog domain and digital domain with mismatch error shaping, including a DAC, a first injection circuit coupled to the DAC, and a second injection circuit coupled to the DAC. The DAC generates a first analog value in response to a first digital value, and generates a second analog value in response to a second digital value. The first injection circuit enables an analog injection value to be injected to the second analog value when the DAC generates the second analog value, wherein the analog injection value is converted from a digital injection value formed by a subset of bits of the first digital value. The second injection circuit injects the digital injection value to the second digital value, or combines the digital injection value and a related value obtained according to the second analog value.

The invention to mismatch and ISI shaping in a data converter. The invention provides a dynamic element matching technique that incorporates both mismatch and inter symbol interference shaping. A digital decoder is provided that controls the number of on and off transitions so that the resulting signal does not contain noise or distortion. The element selection technique of the invention is suitable for high resolution multi-bit continuous time oversampling data converters.

The invention provides a system for conversion between analog domain and digital domain with mismatch error shaping, including a DAC, a first injection circuit coupled to the DAC, and a second injection circuit coupled to the DAC. The DAC generates a first analog value in response to a first digital value, and generates a second analog value in response to a second digital value. The first injection circuit enables an analog injection value to be injected to the second analog value when the DAC generates the second analog value, wherein the analog injection value is converted from a digital injection value formed by a subset of bits of the first digital value. The second injection circuit injects the digital injection value to the second digital value, or combines the digital injection value and a related value obtained according to the second analog value.

An RF transmitter module for a cellular radio that includes a delta-sigma modulator having a plurality of interleaving dynamic element matching (DEM) circuits providing interleaved digital bits at a reduced clock rate. An interleaver controller controls the DEM circuits so as to provide groups of the digital bits at different points in time. In one embodiment, a summation junction adds the groups of the digital bits to provide a continuous stream of the interleaved digital bits, a DAC converts the stream of interleaved digital bits to an analog signal, and a power amplifier amplifies the analog signal.

A cellular radio architecture for a vehicle that includes a programmable bandpass sampling radio frequency front-end and an optimized digital baseband. The architecture includes a triplexer having signal paths that include a bandpass filter that passes a different frequency band than the other bandpass filters and a circulator that provides signal isolation between the transmit signals and the receive signals. The architecture also includes a receiver module having a separate signal channel for each of the signal paths in the triplexer, where each signal channel in the receiver module includes a receiver delta-sigma modulator that converts analog receive signals to a representative digital signal. The architecture further includes a transmitter module having a transmitter delta-sigma modulator for converting digital data bits to analog transmit signals, where the transmitter module includes a power amplifier and a switch for directing the transmit signals to one of the signal paths in the triplexer.

The invention provides a system for conversion between analog domain and digital domain with mismatch error shaping, including a DAC, a first injection circuit couple to the DAC, and a second injection circuit coupled to the DAC. The DAC generates a first analog value in response to a first digital value, and generates a second analog value in response to a second digital value. The first injection circuit enables an analog injection value to be injected to the second analog value when the DAC generates the second analog value, wherein the analog injection value is converted from a digital injection value formed by a subset of bits of the first digital value. The second injection circuit combines the digital injection value and one of the following: the second digital value and a related value obtained according to the second analog value.