Marvell International Limited

Beijing Unisoc Communications Technology Co., Ltd.

Junshi Qiao

Tao Shui

Dennis Sinitsky

Shafiq M Jamal

Jiewei Lai

Te Han

Pei Wang

Song Chen

Haiqing Zhang

A method for arranging a current source array of a DAC and a layout of a common-source current source array are provided in embodiments of the present disclosure for improving linearity and related performance of the DAC. The method includes, determining a number R of rows and a number C of columns of a common-source current source array; dividing the common-source current source array into M sub-arrays; segmenting the DAC to obtain (2&#x2212;1) groups of thermometer encoding current sources and Y groups of binary encoding current sources; arranging the (2&#x2212;1) groups of the thermometer encoding current sources into the M sub-arrays, arranging Y groups of binary encoding current sources into the M sub-arrays based on a number of binary encoding current sources in each of Y groups; arranging bias current sources evenly into the common-source current source array; and arranging other current sources as dummy cells.

Method for arranging current source array of digital-to-analog converter and layout of common-source current source array

An RC oscillator is provided for improving stability of oscillation frequency. The circuit includes an input module, an oscillating module, an inverting module, first and second compensating modules and an output module, wherein the input module provides two-path charging currents and bias current for the oscillating module; the oscillating module outputs a first high level or a first low level to the inverting module under the control of the two-path charging currents and bias current, and improves frequency tuning accuracy of the oscillator; the inverting module inverts the first high level to a second low level or inverts the first low level to a second high level, and outputs the second low level or the second high level to the output module; the output module outputs the second high level and the second low level; and the first and second compensating modules improve stability of the oscillation frequency.

Resistor-capacitor oscillator

A resonant element driver circuit includes a NMOS transistor and a PMOS transistor that are configured to drive a resonant element. The resonant element driver circuit includes biasing circuitry that is configured to bias the PMOS transistor. The biasing circuitry receives a reference signal that is used to set the biasing on the PMOS transistor. The resonant element driver further includes mirror circuitry that tracks current flowing through the NMOS and PMOS transistors.

Class-AB XTAL circuit

Aspects of the disclosure provide a circuit. The circuit includes a signal amplifying circuit coupled with a crystal component of a natural frequency to form a crystal oscillator, and a signal generator circuit configured to generate a signal with an energy distribution about the natural frequency, and to provide the signal to the crystal oscillator to assist the crystal oscillator to begin oscillating.

Growing community of inventors

Shanghai, China

Junshi Qiao