Invention Grant
- Patent Title: Adjustable time duration for driving pulse-width modulation (PWM) output to reduce thermal noise
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Application No.: US15491476Application Date: 2017-04-19
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Publication No.: US09847773B2Publication Date: 2017-12-19
- Inventor: John L. Melanson , Paul Lesso
- Applicant: Cirrus Logic, Inc.
- Applicant Address: US TX Austin
- Assignee: Cirrus Logic, Inc.
- Current Assignee: Cirrus Logic, Inc.
- Current Assignee Address: US TX Austin
- Agency: Norton Rose Fulbright US LLP
- Main IPC: H03K3/01
- IPC: H03K3/01 ; H03K3/011

Abstract:
Noise introduced in an output signal of a pulse-width modulator (PWM) may be reduced by changing the time duration that a switch is driving the output node. Because the power supplies coupled to the switches are the source of noise in the output signal of the PWM, the time duration that the power supplies are driving the output may be reduced to obtain a subsequent reduction in noise in the output signal. For example, when a small signal is desired to be output by the PWM, the switches may be operated for shorter time durations. Thus, the switches couple the noise sources to ground for a duration of a cycle to reduce contribution of noise to the output. But, when a larger signal is desired to be output by the PWM, the switches may be operated for longer time durations or the conventional time durations described above.
Public/Granted literature
- US20170222629A1 ADJUSTABLE TIME DURATION FOR DRIVING PULSE-WIDTH MODULATION (PWM) OUTPUT TO REDUCE THERMAL NOISE Public/Granted day:2017-08-03
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