Mediatek Corporation

Jen-Che Tsai

Sheng-Hao Chen

Paul Cheng Po Liang

Sheng-Hong Yan

Yau-Wai Wong

Chao-Hsin Lu

Sheng-Jui Huang

Yung-Yu Lin

Tzueng-Yau Lin

Yen-Chuan Huang

Chi-Hui Wang

Chun-Hao Liao

Min-Hua Wu

Chi Yun Wang

Hung-Pin Ma

Tzu-Hao Yu

Shu-Wei Chu

Chih-Horng Weng

A radio frequency (RF) receiver includes a digital tuning engine; and I-path and Q-path analog filters, tuned by the digital tuning engine. The digital tuning engine gets an I/Q imbalance difference, and the digital tuning engines tunes the I-path analog filter and/or the Q-path analog filter based on the I/O imbalance difference.

RF receiver and digitally-assisted calibration method applicable thereto

A SAR ADC including a comparator, an input switch unit, a positive conversion capacitor array, a negative conversion capacitor array, and a SAR controller is provided. The input switch unit alternately couples and decouples a differential analog input signal to the comparator. The positive and negative conversion capacitor arrays sample the differential analog input signal during the sampling phase. The SAR controller resets the switches in the capacitor arrays at the end of the sampling phase to change the sampled voltage into a residual signal, generates an intermediate digital code to control the switches during the conversion phase according to an output of the comparator to convert the residual signal to the intermediate digital code, generates the digital code according to the intermediate digital code, and uses an inverted intermediate digital code to control the switches at the end of the conversion phase.

SAR ADC and method thereof

A radio frequency (RF) receiver includes a digital tuning engine; I-path and Q-path analog filters, tuned by the digital tuning engine; and a digital compensation circuit. The digital tuning engine executes a RC (resistor-capacitor) time constant calibration to adjust respective cut-off frequencies of the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter mismatch calibration to match the I-path analog filter and the Q-path analog filter. The digital tuning engine executes a filter residual mismatch calibration to match an I-path response from the I-path analog filter to the digital compensation circuit and a Q-path response from the Q-path analog filter to the digital compensation circuit.

A digital to analog converting system, which comprises: a first data converting circuit, for receiving a first digital data stream transmitted at a first clock frequency, for converting the first digital data stream to a plurality of second digital data streams transmitted at a second clock frequency, and for outputting the second digital data streams in parallel; a second data converting circuit, for receiving the second digital data streams from the first data converting circuit, and for converting the second digital data streams to a third digital data stream transmitted at a third clock frequency; and a first digital to analog converter, for converting the third digital data stream to a first output analog data stream. The second clock frequency is lower than the first clock frequency and the third clock frequency.

Digital to analog converting system and digital to analog converting method

A method of controlling a successive-comparing-register analog-to-digital convertor (SAR ADC) is provided. Based upon the method, the SAR ADC receives a conversion clock that controls a conversion rate of the SAR ADC.

Successive-approximation-register analog-to-digital convertor and related controlling method

A continuous-time delta-sigma Analog to Digital Converter (ADC) includes: a loop filter, for receiving and noise-shaping an analog input signal, and outputting a first loop voltage; a first summing resistor, for transforming a first feedback current to be a first feedback voltage, and summing the first loop voltage and the first feedback voltage so as to generate a first summing voltage, wherein the first summing voltage is equal to a sum of the first loop voltage and the first feedback voltage; a quantizer, for outputting a digital output signal according to the first summing voltage; and a current Digital to Analog Converter (DAC), for generating the first feedback current according to the digital output signal.

Continuous-time delta-sigma ADC with compact structure

A signal processing system and related method are disclosed. The signal processing system includes a signal processing module, powered by a low supply voltage, for processing signals; and an interface module, coupled to the signal processing module, powered by a high supply voltage, for outputting signals generated from the signal processing module; wherein the interface module comprises a plurality of high-voltage functional blocks integrated therein, and each of the functional blocks is configured to perform a predetermined interface functionality. In this way, the bill-of-material (BOM) cost can be reduced.

Signal processing system having a plurality of high-voltage functional blocks integrated into interface module and method thereof

An apparatus and a muting circuit. The apparatus comprises an amplifier, a mute circuit, a pull-down circuit, and a power detection circuit. The amplifier receives a power supply voltage and a common mode voltage, and amplifies an audio input signal to generate an audio output signal. The mute circuit, coupled to the amplifier, conducts the audio output signal to about ground level upon receiving a mute signal. The pull-down circuit, coupled to the amplifier, pulls the common mode voltage to about ground level upon receiving a pull-down signal. The power detection circuit, coupled to the mute circuit and the pull-down circuit, detects power-up or power-down of the power supply voltage, and generates the mute signal and a pull-down signal according to the power-up or power-down operation.

Apparatus and muting circuit

A clock timing calibration circuit includes a clock timing adjusting unit and a calibration control unit. The clock timing adjusting unit is for receiving an incoming reference clock signal and selectively adjusting the received reference clock signal to generate a first clock signal according to a calibration control signal. The incoming reference clock has a predetermined phase and a predetermined frequency, The calibration control unit is for checking if the phase difference between the first clock signal and a second clock signal satisfies a predetermined criterion, and for adjusting the calibration control signal when the phase difference between the first clock signal and the second clock signal does not satisfy the predetermined criterion. The predetermined criterion is to check if the phase difference falls within a specific range associated with a clock period of one of the first clock signal and the second clock signal.

Clock timing calibration circuit and clock timing calibration method for calibrating phase difference between different clock signals and related analog-to-digital conversion system using the same

A continuous-time delta-sigma Analog to Digital Converter (ADC) with a compact structure comprises a loop filter, a summing circuit, a quantizer, and a current Digital to Analog Converter (DAC). The loop filter is utilized for receiving and noise-shaping an analog input signal, and accordingly outputting a positive and a negative loop voltages. The summing circuit comprises a positive and a negative summing resistors. The summing resistors are utilized for transforming a positive and negative feedback currents to be a positive and a negative feedback voltages, and summing the loop voltages and the feedback voltages so as to generate a positive and a negative summing voltages, respectively. The quantizer is utilized for outputting a digital output signal according to a difference between the positive and the negative summing voltages. The current DAC is utilized for generating the positive and the negative feedback currents according to the digital output signal.

A digital to analog converter including a first capacitor, a second capacitor, an operational amplifier, and a switch is disclosed. During a first period, the first capacitor stores a first voltage and the second capacitor stores a second voltage. The operational amplifier comprises an input and an output. The switch parallels the first and the second capacitors with the operational amplifier at the input and output according to a digital signal during a second period.

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Taichung, Taiwan

Jen-Che Tsai