Linearizer Circuits and Methods for Audio Switches
AssigneeQUALCOMM Incorporated
InventorsChienchung YANG, Khaled Mahmoud ABDELFATTAH ALY, Vijayakumar DHANASEKARAN
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Abstract
A wireless device may include a plug that is shared by high speed data, analog audio signals, and power. Switches may be included on wires between the plug and the circuits that provide the high-speed data, analog audio signals and power to isolate those circuits from overvoltage conditions. Linearizer circuits may be included to provide gate driving signals to the switches, e.g., during transmission of analog audio signals. The linearizer circuits may include digital-to-analog converters to apply a gain factor to analog audio signals.
Claims30
A wireless communication device comprising:
- an application processor;
- a first audio signal amplifier;
- multiplexing circuitry configured to couple the application processor and the first audio signal amplifier to a set of wires;
- a data and audio plug coupled to the set of wires;
- a first metal oxide semiconductor field effect transistor (MOSFET) switch disposed on a first wire of the set of wires between the first audio signal amplifier and the data and audio plug;
- and
- a first gate driving circuit having an output coupled to a gate of the first MOSFET switch, the first gate driving circuit including a first buffer having a first buffer input coupled to an output of the first audio signal amplifier through a first digital-to-analog converter (DAC).
A method for operating wireless communication device having a first metal oxide semiconductor (MOSFET) switch implemented between a first audio signal amplifier and an audio load, the method comprising:
- isolating the first audio signal amplifier from the audio load, including applying a first gate control signal to the first MOSFET switch at a first voltage level that turns off the first MOSFET switch;
- and
- linearizing the first MOSFET switch, including applying the first gate control signal to the first MOSFET switch at a second voltage level during an ON state of the first MOSFET switch, wherein linearizing the first MOSFET switch includes applying an output of the first audio signal amplifier as a reference voltage to a first digital-to-analog converter (DAC), wherein the first DAC applies a first gain level to the output of the first audio signal amplifier, and wherein a first amplifier receives the output of the first audio signal amplifier at the first gain level, and wherein the first amplifier outputs the first gate control signal to the first MOSFET switch.
A wireless communication device comprising:
- means for running an operating system;
- means for amplifying analog audio signals;
- means for coupling the means for running the operating system and the means for amplifying analog audio signals to a set of wires;
- a data and audio plug coupled to the set of wires;
- a first transistor coupled between the data and audio plug and the means for amplifying analog audio signals;
- and
- means for linearizing operation of the first transistor, the means for linearizing operation of the first transistor including a first digital-to-analog converter (DAC) configured to receive a first audio signal from the means for amplifying analog audio signals and outputting the first audio signal having a first gain level to a first amplifier, wherein the first amplifier is coupled to a gate of the first transistor.
A wireless communication device comprising:
- an application processor;
- a pair of audio signal amplifiers corresponding to a first audio channel and a second audio channel;
- a coder decoder (codec) chip having multiplexing circuitry configured to couple the application processor and the pair of audio signal amplifiers to a set of wires;
- a plug coupled to the set of wires;
- a first switch coupled between the application processor and the plug on a first wire of the set of wires;
- and
- a first gate driving circuit having an output coupled to a gate of the first switch, the first gate driving circuit including a first buffer having a first buffer input coupled to the first audio channel through a first digital-to-analog converter (DAC).
Dependencies are inferred from the claim text.