Invention Grant
- Patent Title: Direct current mode digital-to-analog converter to class D amplifier
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Application No.: US16175907Application Date: 2018-10-31
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Publication No.: US10397701B2Publication Date: 2019-08-27
- Inventor: Lars Risbo , Ryan Erik Lind , Jasjot Singh Chadha
- Applicant: TEXAS INSTRUMENTS INCORPORATED
- Applicant Address: US TX Dallas
- Assignee: TEXAS INSTRUMENTS INCORPORATED
- Current Assignee: TEXAS INSTRUMENTS INCORPORATED
- Current Assignee Address: US TX Dallas
- Agent John R. Pessetto; Charles A. Brill; Frank D. Cimino
- Main IPC: H04R3/00
- IPC: H04R3/00 ; H04R3/02 ; H03F3/217 ; H03F3/185 ; H03F3/30 ; H03F3/45

Abstract:
A system includes a class D amplifier and a current steering digital-to-analog converter (DAC) directly connected to the class D amplifier. The system also includes a common mode servo circuit coupled to a node interconnecting the current steering DAC to the class D amplifier. The common servo circuit amplifies a difference between a common mode signal determined from the node and a reference voltage and generates a feedback current to the node based on the amplified difference. A feed-forward common-mode compensation circuit is included to reduce an alternating current (AC) ripple from the class D amplifier. The feed-forward common-mode compensation circuit includes first and second resistors coupled to respective outputs of the class D amplifier. A current mirror is coupled to the first and second resistors and is configured to sink a current from the node to ground that approximates a common mode feedback current of the class D amplifier.
Public/Granted literature
- US20190069087A1 Direct Current Mode Digital-to-Analog Converter to Class D Amplifier Public/Granted day:2019-02-28
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