Disclosed are an analog-to-digital converter error shaping circuit and a successive approximation analog-to-digital converter. The analog-to-digital converter error shaping circuit includes a decentralized capacitor array, a data weighted average module, a mismatch error shaping module, a control logic generation circuit, a digital filter and a decimator. The decentralized capacitor array includes two symmetrically arranged capacitor array units, each capacitor array unit includes a first sub-capacitor array of a high segment bit and a second sub-capacitor array of a low segment bit. The data weighted average module is configured to eliminate correlation between the first sub-capacitor array and an input signal, and the mismatch error shaping module is configured to eliminate correlation between the second sub-capacitor array and the input signal.

Methods, systems, and devices for thermometer coding for driving non-binary signals are described. A set of drivers may be used to drive a signal line, with each of the drivers calibrated to have different individual drive strengths. To drive a signal line to successive voltages in accordance with a non-binary modulation scheme, additional individual drivers of the set may be used. The different drive strengths of the individual drivers of the set may scale in non-linear fashion, which may offset non-linearities associated with the individual drivers as additional individual drivers of the set are activated.

A dynamic element method includes the following operations: summing up most significant bits of a digital code in a previous period and a pointer signal in the previous period, in order to generate a first signal; outputting the first signal to be an adjusted pointer signal according to a clock signal; and decoding the adjusted pointer signal to be control signals, in which the control signals are configured to set corresponding relations of components of a first digital to analog converter circuits and the most significant bits, in order to utilize the components to convert the most significant bits.

Memory units are accessed using address bits. The address bits used to access memory units can have various formats. The address bits to access successive locations that are to be sequentially accessed can have a reduced Hamming distance binary code format to reduce a quantity of toggling to switch from one set of address bits to another set of address bits.

Memory units are accessed using address bits. The address bits used to access memory units can have various formats. The address bits to access successive locations that are to be sequentially accessed can have a reduced Hamming distance binary code format to reduce a quantity of toggling to switch from one set of address bits to another set of address bits.

A digital-to-analog conversion circuit includes a first digital-to-analog converter (DAC) and a second DAC. The first DAC includes a first current generation circuit (CGC) and a first current-to-voltage converter. The first CGC generates a first current based on a first digital code received through a first terminal to provide the first current to an output node. The second DAC includes a second CGC and a second current-to-voltage converter. The second CGC generates a second current based on a second digital code received through a second input terminal to provide the second current to the output node. The first current-to-voltage converter and the second current-to-voltage converter convert a sum of the first current and the second current to a an analog voltage corresponding to a sum of the first digital code and the second digital code, and output the analog voltage at the output node.

A bi-directional Gray code counter includes a first set of logic circuitry configured to receive an input having a first sequence of bits representing a first value. The first set of logic circuitry is further configured to convert the first sequence of bits to a second sequence of bits representing the first value. The bi-directional Gray code counter further includes a second set of logic circuitry and third second set of logic circuitry. The second set of logic circuitry is configured to compare the second sequence of bits to a bit index pattern. The third set of logic circuitry is configured to transition one bit in the first sequence of bits from a first state to a second state to form a third sequence of bits representing a second value. The one bit is transitioned in response to the second sequence of bits being compared to the bit index pattern.

A bi-directional Gray code counter includes a first set of logic circuitry configured to receive an input having a first sequence of bits representing a first value. The first set of logic circuitry is further configured to convert the first sequence of bits to a second sequence of bits representing the first value. The bi-directional Gray code counter further includes a second set of logic circuitry and third second set of logic circuitry. The second set of logic circuitry is configured to compare the second sequence of bits to a bit index pattern. The third set of logic circuitry is configured to transition one bit in the first sequence of bits from a first state to a second state to form a third sequence of bits representing a second value. The one bit is transitioned in response to the second sequence of bits being compared to the bit index pattern.

An example method may include obtaining multiple symbols each associated with a different state in a quadrature amplitude modulation scheme used for transmission of a data signal. The method may further include determining a sequence of symbols of the multiple symbols for a first portion of the data signal. The determining may include selecting an index value from multiple index values for the first portion of the data signal. The determining may also include obtaining energy states of multiple sequences of the symbols using the energy levels of the symbols. The determining may further include obtaining a relationship between the energy levels of the symbols, the energy states of the multiple sequences of the symbols, and the multiple index values. The determining may further include selecting the sequence of symbols based on the relationship and the index value for the first portion of the data signal.

Aspects of the technology described herein related to an ultrasound processing unit (UPU) including gray-coding circuitry configured to convert standard binary-coded digital ultrasound signals to gray-coded digital ultrasound signals and gray-decoding circuitry coupled to the gray-coding circuitry and configured to convert the gray-coded digital ultrasound signals to standard binary-coded digital ultrasound signals. The UPU may include an analog portion, a digital portion, and a data bus configured to route the gray-coded digital ultrasound signals from the analog portion to the digital portion subsequent to converting the standard binary-coded digital ultrasound signals to the gray-coded digital ultrasound signals. The analog portion may include multiple analog front-ends (AFEs), the gray-coding circuitry, and an analog-to-digital converter. The digital portion may include the gray-decoding circuitry. A data bus from one AFE may pass over another AFE.