Systems and methods are disclosed for Successive Approximation Register Analog-to-Digital Converter (SAR ADC) by coupling an ADC capacitive network coupled to a comparator; and performing binary search using a comparator output using a capacitive DAC calibration process to enhance SAR ADC linearity and performance. In one implementation, the calibration process starts with the least significant bit (LSB) capacitor calibration then proceed to higher bit capacitors until all the capacitors are calibrated. Each capacitor consists of fixed-value base capacitor and value-adjustable capacitor. The capacitor calibration logic is implemented based on the process then incorporated into SAR ADC. ADC performs capacitor calibration first before normal conversion operation. The non-ideal aspect of normal conversion operation is preserved and accounted during capacitor calibration. By employing capacitor calibration, the DAC capacitor value can be minimal to enhance settling and conversion rate, SAR ADC performance is improved.

Systems and methods are disclosed for Successive Approximation Register Analog-to-Digital Converter (SAR ADC) by coupling an ADC capacitive network coupled to a comparator; and performing binary search using a comparator output using a capacitive DAC calibration process to enhance SAR ADC linearity and performance. In one implementation, the calibration process starts with the least significant bit (LSB) capacitor calibration then proceed to higher bit capacitors until all the capacitors are calibrated. Each capacitor consists of fixed-value base capacitor and value-adjustable capacitor. The capacitor calibration logic is implemented based on the process then incorporated into SAR ADC. ADC performs capacitor calibration first before normal conversion operation. The non-ideal aspect of normal conversion operation is preserved and accounted during capacitor calibration. By employing capacitor calibration, the DAC capacitor value can be minimal to enhance settling and conversion rate, SAR ADC performance is improved.

The present invention relates to telecommunication techniques and integrated circuit (IC) devices. In a specific embodiment, the present invention provides a laser deriver apparatus that includes a main DAC section and a mini DAC section. The main DAC section processes input signal received from a pre-driver array and generates an intermediate output signal. The mini DAC section provides a compensation signal to reduce distortion of the intermediate output signal. The intermediate output signal is coupled to output terminals through a cascode section and/or a T-coil section. There are other embodiments as well.

The present invention relates to telecommunication techniques and integrated circuit (IC) devices. In a specific embodiment, the present invention provides a laser deriver apparatus that includes a main DAC section and a mini DAC section. The main DAC section processes input signal received from a pre-driver array and generates an intermediate output signal. The mini DAC section provides a compensation signal to reduce distortion of the intermediate output signal. The intermediate output signal is coupled to output terminals through a cascode section and/or a T-coil section. There are other embodiments as well.

Systems and methods are disclosed for Successive Approximation Register Analog-to-Digital Converter (SAR ADC) by coupling an ADC capacitive network coupled to a comparator; and performing binary search using a comparator output using a capacitive DAC calibration process to enhance SAR ADC linearity and performance. In one implementation, the calibration process starts with the least significant bit (LSB) capacitor calibration then proceed to higher bit capacitors until all the capacitors are calibrated. Each capacitor consists of fixed-value base capacitor and value-adjustable capacitor. The capacitor calibration logic is implemented based on the process then incorporated into SAR ADC. ADC performs capacitor calibration first before normal conversion operation. The non-ideal aspect of normal conversion operation is preserved and accounted during capacitor calibration. By employing capacitor calibration, the DAC capacitor value can be minimal to enhance settling and conversion rate, SAR ADC performance is improved.

The present invention discloses a DAC method having signal calibration mechanism is provided. Operation states of current sources are controlled to generate an output analog signal by a DAC circuit according to a codeword of an input digital signal. An echo signal is generated by an echo transmission circuit according to the output analog signal. The codeword is mapped to generate an offset signal by a calibration circuit according to a codeword offset mapping table. The offset signal is processed to generate an echo-canceling signal by an echo-canceling circuit. By a calibration parameter calculation circuit, offset amounts are generated according to a difference between the echo signal and the echo-canceling signal, the offset amounts are grouped to perform statistic operation according to the operation states and current offset values are calculated according to calculation among groups and converted to codeword offset values to update the codeword offset mapping table.

A self-calibrating Analog-to-Digital Converter (ADC) performs radix error calibration using a Successive-Approximation Register (SAR) to drive test voltages onto lower-significant capacitors. The final SAR code is corrected by performing LSB averaging on LSB averaging capacitors and then accumulated, and the measurement repeated many times to obtain a digital average measurement. An ideal radix or ratio of the measured capacitor's capacitance to a unit capacitance of an LSB capacitor is subtracted from the digital average measurement to obtain a measured error that is stored in a Look-Up Table (LUT) with the ideal radix. Radix error calibration is repeated for other capacitors to populate the LUT. During normal ADC conversion, the SAR code obtained from converting the analog input is applied to addresses the LUT, and all ideal radixes and measured errors for 1 bits in the SAR code are added together to generate an error-corrected digital value.

An analog-to-digital converter (ADC) includes a digital-to-analog converter (DAC) and a comparator having a first input coupled to receive an output voltage of the DAC, a second input, and a comparison output. The ADC also includes successive-approximation-register (SAR) circuitry having an input to receive the comparison output, and an output to provide an uncalibrated digital value. The DAC includes a Most Significant Bits (MSBs) sub-DAC including a set of MSB DAC elements and a Least Significant Bits (LSBs) sub-DAC including a set of LSB DAC elements. The ADC also includes calibration circuitry which receives the uncalibrated digital value and applies one or more calibration values to the uncalibrated digital value to obtain a calibrated digital value. The calibration circuitry obtains a calibration value for each MSB DAC element using the set of LSB DAC elements, the termination element, and at least one of the one or more redundant DAC elements.

A first and second input tone are applied to a continuous-time complex filter within an integrated circuit. The magnitude of the output of the filter at the frequency of each of the first and second input tones are measured and compared to determine the value of a filter tuning control signal. A tuning control signal is applied to the filter with the determined value to tune the filter.

A calibrating digital to analog converter (calDAC) architecture uses a low voltage memory to store the digital inputs of calDACs. The calDAC architecture includes a low voltage domain and a high voltage domain coupled to the low voltage domain. The low voltage domain includes a calDAC memory and a finite state machine (FSM). The high voltage domain includes a calDAC core, an interface circuit, and a bias control circuit coupled to the interface circuit. The interface circuit may be provided between the calDAC core and the low voltage domain. The bias control circuit is coupled to the interface circuit to generate a bias voltage for the interface circuit to drive switch transistors of the calDAC core.