公开(公告)号：US09912144B2

公开(公告)日：2018-03-06

申请号：US14477236

申请日：2014-09-04

Applicant: ANALOG DEVICES TECHNOLOGY

Inventor： Trevor Clifford Caldwell ,  Corey Petersen ,  David Nelson Alldred ,  Hajime Shibata

IPC: H03M1/12 ,  H02H7/12 ,  H03M3/00

CPC classification number: H02H7/12 ,  H03M3/30 ,  H03M3/36 ,  H03M3/464 ,  H03M3/484

Abstract: Delta-sigma modulators do not handle overload well, and often become unstable if the input goes beyond the full-scale range of the modulator. To provide overload protection, an improved technique embeds an overload detector in the delta sigma modulator. When an overload condition is detected, coefficient(s) of the delta sigma modulator is adjusted to accommodate for the overloaded input. The improved technique advantageously allows the delta sigma modulator to handle overload gracefully without reset, and offers greater dynamic range at reduced resolution. Furthermore, the coefficient(s) of the delta sigma modulator can be adjusted in such a way to ensure the noise transfer function is not affected.

公开(公告)号：US20150123828A1

公开(公告)日：2015-05-07

申请号：US14073396

申请日：2013-11-06

Applicant: ANALOG DEVICES TECHNOLOGY

Inventor： David Nelson Alldred ,  Jipeng Li ,  Richard E. Schreier ,  Hajime Shibata

IPC: H03M3/00 ,  H03M1/18

CPC classification number: H03M3/442 ,  H03M3/43 ,  H03M3/454

Abstract: In one example implementation, the present disclosure provides a loop filter for use in a continuous-time sigma-delta analog-to-digital converter. Specifically, a capacitive feedback digital-to-analog converter path is provided at the input of a first opamp in a series of opamp integrators. The capacitive feedback digital-to-analog converter at the input of the first opamp reduces the signal content at the output of the first opamp, and thereby reduces the output swing of the first opamp. A reduction in output swing provides a more efficient loop filter.

Abstract translation: 在一个示例实现中，本公开提供了一种在连续时间Σ-Δ模数转换器中使用的环路滤波器。 具体地，在一系列运算放大器积分器中的第一运算放大器的输入处提供电容反馈数模转换器路径。 在第一运算放大器的输入处的电容反馈数模转换器减少了第一运算放大器的输出处的信号内容，从而减小了第一运算放大器的输出摆幅。 输出摆幅的减小提供了更有效的环路滤波器。

公开(公告)号：US09054731B2

公开(公告)日：2015-06-09

申请号：US14073396

申请日：2013-11-06

Applicant: ANALOG DEVICES TECHNOLOGY

Inventor： David Nelson Alldred ,  Jipeng Li ,  Richard E. Schreier ,  Hajime Shibata

IPC: H03M3/00 ,  H03M1/18

CPC classification number: H03M3/442 ,  H03M3/43 ,  H03M3/454

Abstract: In one example implementation, the present disclosure provides a loop filter for use in a continuous-time sigma-delta analog-to-digital converter. Specifically, a capacitive feedback digital-to-analog converter path is provided at the input of a first opamp in a series of opamp integrators. The capacitive feedback digital-to-analog converter at the input of the first opamp reduces the signal content at the output of the first opamp, and thereby reduces the output swing of the first opamp. A reduction in output swing provides a more efficient loop filter.

Abstract translation: 在一个示例实现中，本公开提供了一种在连续时间Σ-Δ模数转换器中使用的环路滤波器。 具体地，在一系列运算放大器积分器中的第一运算放大器的输入处提供电容反馈数模转换器路径。 在第一运算放大器的输入处的电容反馈数模转换器减少了第一运算放大器的输出处的信号内容，从而减小了第一运算放大器的输出摆幅。 输出摆幅的减小提供了更有效的环路滤波器。