Patent classifications
H03M1/0863
Analog-to-digital converter arrangement
An analog-to-digital converter arrangement may include an analog amplifier with variable gain; an analog-to-digital converter; a digital reconstruction element including elements to reduce an influence of transients during a change of the variable gain of the analog amplifier.
ANALOG-TO-DIGITAL CONVERTING CIRCUIT RECEIVING REFERENCE VOLTAGE FROM ALTERNATIVELY SWITCHED REFERENCE VOLTAGE GENERATORS AND REFERENCE VOLTAGE CAPACITORS AND OPERATING METHOD THEREOF
An analog-to-digital converting circuit for converting an analog signal into a digital signal includes a plurality of reference voltage generators each generating a reference voltage, a plurality of reference voltage decoupling capacitors respectively corresponding to the reference voltage generators, and an analog-to-digital converter generating a comparison voltage based on the reference voltage and generating the digital signal corresponding to the analog signal based on a result of comparing the comparison voltage with the analog signal. At least one different combination of the reference voltage generators and the reference voltage decoupling capacitors is connected to the analog-to-digital converter in each of a plurality of conversion periods.
FDAC/2 SPUR ESTIMATION AND CORRECTION
A spur correction system for a transmit chain having an interleaving multiplexer. In some embodiments, the spur correction system includes a spur sense chain, a correction controller, and a Q path corrector. The interleaving multiplexer combines signals from multiple bands in response to a clock signal. The spur sense chain estimates an error that is in phase with the clock signal (an I-phase error) and an error that is a derivative of the clock signal (a Q-phase error). The correction controller compensates for the estimated I-phase error by injecting an I-phase correction signal into the transmit chain. The Q path corrector compensates for the estimated Q-phase error by selectively connecting one or more capacitors within the interleaving multiplexer.
Adaptive analog to digital converter (ADC) multipath digital microphones
Exemplary multipath digital microphone described herein can comprise exemplary embodiments of adaptive ADC range multipath digital microphones, which allow low power to be achieved for amplifiers or gain stages, as well as for exemplary adaptive ADCs in exemplary multipath digital microphone arrangements described herein, while still providing a high DR digital microphone systems. Further non-limiting embodiments can comprise an exemplary glitch removal component configured to minimize audible artifacts associated with the change in the gain of the exemplary adaptive ADCs.
BRIDGE SENSOR DC ERROR CANCELLATION SCHEME
The disclosed techniques provide a number of technical benefits by providing a bridge sensor DC error cancellation scheme. In one embodiment, a system includes a piezoresistive Wheatstone bridge, a number of switches, and a non-overlapping clock. The system can mitigate noise and other errors by subtraction of the two differential outputs of the system between a first phase and a second phase of a clock input controlling the switches. In some embodiments, the system can also include differential programmable gain amplifiers and a multi-bit analog-to-digital converter. By providing a bridge sensor DC error cancellation scheme for producing an analog output, a system can be used to generate a stable digital output of at the analog-to-digital converter.
REFERENCE VOLTAGE BUFFER CIRCUIT
A reference voltage buffer circuit is provided, which could improve the reliability of the reference voltage buffer circuit, including: at least one output branch, where each output branch includes a delay control branch, a first MOSFET, and a second MOSFET; and a feedback branch, where in a first time period, the feedback branch is configured to output a first voltage to the delay control branch, and the delay control branch is configured to control the first MOSFET and the second MOSFET to be turned on, such that a source of the first MOSFET continuously outputs a reference voltage; and in a second time period, a voltage output from the feedback branch to the delay control branch is 0, the delay control branch is configured to control the second MOSFET to be turned off before the first MOSFET is turned off.
DIGITAL-TO-ANALOG CONVERTER (DAC)-BASED VOLTAGE-MODE TRANSMIT DRIVER ARCHITECTURE WITH TUNABLE IMPEDANCE CONTROL AND TRANSITION GLITCH REDUCTION TECHNIQUES
A digital-to-analog converter (DAC)-based voltage-mode transmit driver architecture. One example transmit driver circuit generally includes an impedance control circuit coupled to a plurality of DAC driver slices. The impedance control circuit generally includes a tunable impedance configured to be adjusted to match a load impedance for the transmit driver circuit. Another example transmit driver circuit generally has an output impedance that is smaller than the load impedance for the transmit driver circuit, such that an output voltage swing at differential output nodes of the transmit driver circuit is greater than a voltage of a power supply rail. Another example transmit driver circuit generally includes a predriver circuit with a first inverter coupled to a first output of the predriver circuit and a second inverter coupled to a second output of the predriver circuit, the transistors in at least one of the first inverter or the second inverter having different strengths.
ANALOG-TO-DIGITAL CONVERTER SYSTEM USING REFERENCE ANALOG-TO-DIGITAL CONVERTER WITH SAMPLING POINT SHIFTING AND ASSOCIATED CALIBRATION METHOD
An analog-to-digital converter (ADC) system includes a main ADC, a reference ADC, a sampling control circuit, and a calibration circuit. The main ADC obtains a first sampled input voltage by sampling an analog input according to a first sampling clock, and performs analog-to-digital conversion upon the first sampled voltage to generate a first sample value. The reference ADC obtains a second sampled voltage by sampling the analog input according to a second sampling clock, and performs analog-to-digital conversion upon the second sampled voltage to generate a second sample value. The sampling control circuit controls the second sampling clock to ensure that the second sampling clock and the first sampling clock have a same frequency but different phases, and adjusts the second sample value to generate a reference sample value. The calibration circuit applies calibration to the main ADC according to the first sample value and the reference sample value.
Mismatch and timing correction technique for mixing-mode digital-to-analog converter (DAC)
Certain aspects of the present disclosure generally relate to circuitry and techniques for digital-to-analog conversion. For example, certain aspects provide an apparatus for digital-to-analog conversion. The apparatus generally includes a mixing-mode digital-to-analog converter (DAC), a duty cycle adjustment circuit having an input coupled to an input clock node and having an output coupled to a clock input of the mixing-mode DAC, and a current comparison circuit having inputs coupled to outputs of the mixing-mode DAC and having an output coupled to a control input of the duty cycle adjustment circuit.
Reference voltage generating circuit
The present invention provides a reference voltage generating circuit. The reference voltage generating circuit includes a charge supply circuit providing a first reference voltage during a first period; and a voltage supply circuit providing a second reference voltage during a second period. The voltage supply circuit does not provide the second reference voltage during the first period.