Mediatek Corporation

Shang-Ping Chen

Ping-Ying Wang

Yan-Bin Luo

Chih-Chien Hung

Bo-Jiun Chen

Ding-Shiuan Shen

Bo-Wei Hsieh

Chih-Cheng Chen

Ming-Shi Liou

Hao-Ping Hong

Sheng-Ming Chang

Qui-Ting Chen

A universal serial bus device includes: a core circuit having a first pin and a second pin, and having an input impedance looking into the core circuit from the first pin and the second pin; and a charging control circuit, coupled to the core circuit, arranged for providing a voltage source having a predetermined voltage to one of the first pin and the second pin and for providing a current source having a predetermined current to the other of the first pin and the second pin; wherein the input impedance of the core circuit is configured to make the predetermined voltage and the predetermined current substantially intact when an external charger charges a battery device of the universal serial bus device.

Universal serial bus device and charging and enumeration method

A termination circuit for a plurality of memories controlled by a controller is provided. The termination circuit includes a plurality of drivers, a plurality of resistors and a plurality of capacitors. Each of the drivers is coupled to the memories via a transmission line. Each of the resistors is coupled to the corresponding driver via the corresponding transmission line. Each of the capacitors is coupled between the corresponding resistor and a reference voltage. The controller is coupled to the memories via the drivers, and the controller provides a specific code to one of the drivers when a quantity of logic '0' and a quantity of logic '1' transmitted to the memories via the transmission line corresponding to the one of the drivers are unbalanced, so as to adjust a termination voltage of the capacitor corresponding to the one of the drivers.

Termination circuit and DC balance method thereof

A memory controller is provided. The memory controller is powered by first and second power source and includes an input/output pin, a driver circuit, a terminal resistor, and an input buffer. The driver circuit is coupled to the input/output pin and capable of providing to a writing signal to the input/output pin. The terminal resistor is coupled between the input/output pin and the first power source. The input buffer is coupled to the input/output pin and capable of receiving a reading signal from the input/output pin. No terminal resistor is coupled between the input/output pin and the second power source.

Low power memory controllers

Clock generators are provided. A phase locked loop generates an output clock, a delay line is coupled to an input of the phase locked loop, and a modulation unit integrates an input signal with a constant level to generate a modulation signal controlling the delay line, thereby modulating a phase of a first input clock of the phase locked loop, such that frequency of the output clock is locked at a desired frequency.

Clock generators and clock generation methods thereof

Spread spectrum generators and methods are disclosed. In one implementation, a spread spectrum clock generator includes a phase locked loop generating an output clock according to a first clock and a second clock; a delay line coupled between the first clock and the phase locked loop; a modulation unit providing a modulation signal to control the delay line thereby modulating phase of the first clock, such that frequency of the output clock generated by the phase locked loop varies periodically; a scaling unit scaling the modulation signal from the modulation unit according to a scaling ratio, and outputting to the delay line; and a calibration unit generating an output signal for controlling the scaling ratio.

Spread spectrum clock generators

Spread spectrum clock generators. A phase lock loop generates an output clock according to a first input clock and a second input clock, a delay line is coupled between the first input clock and the phase lock loop. A modulation unit provides a modulation signal to control the delay line thereby modulating phase of the first input clock, such that frequency of the output clock generated by the phase lock loop varies periodically.

A phase-locked loop circuit, including: an operating circuit for detecting a difference between a reference signal and a feedback oscillating signal to generate a detected result, and generating a first control signal according to the detected result, an auxiliary circuit for generating a second control signal that is asynchronous with the first control signal, and a controllable oscillator coupled to the operating circuit and the auxiliary circuit for generating an output oscillating signal according to the first control signal and the second control signal, wherein the feedback oscillating signal is derived from the output oscillating signal.

Phase-locked loop circuit and related phase locking method

A data slicer includes a comparator coupled with an input signal and a reference signal for generating a sliced signal, a waveform generator for generating a calibration signal, a pulse extension device coupled to the comparator and the waveform generator for modifying the duty cycle of the sliced signal or the calibration signal to output, a charge pump coupled between the pulse extension device and a first node for charging and discharging the first node according to the signal output from the pulse extension device, a determining circuit for adjusting the data slicer according to the level change at the first node, and a feedback device coupled between the first node and the comparator for generating the reference signal.

Growing community of inventors

Tai-Chung, Taiwan

Shang-Ping Chen