公开(公告)号：US10432157B2

公开(公告)日：2019-10-01

申请号：US16228926

申请日：2018-12-21

Applicant: Texas Instruments Incorporated

Inventor： Ryan Erik Lind

IPC: G05F1/46 ,  G05F1/56 ,  H03F3/45 ,  H03F1/02 ,  H02M3/04 ,  H02M7/04 ,  H02M1/00 ,  G05F1/575

Abstract: One example includes a transconductor system. The system includes a first transconductance amplifier that generates a control current in response to a first input voltage. The system also includes a second transconductance amplifier that generates an output signal in response to a second input voltage. The system further includes an intermediate amplifier that generates a control voltage in response to the control current and a third input voltage. The control voltage can be provided to the first and second transconductance amplifiers to set a transconductance of each of the first and second transconductance amplifiers to be approximately equal.

公开(公告)号：US20190140606A1

公开(公告)日：2019-05-09

申请号：US16228926

申请日：2018-12-21

Applicant: Texas Instruments Incorporated

Inventor： Ryan Erik Lind

IPC: H03F3/45 ,  H02M7/04 ,  G05F1/46 ,  G05F1/56 ,  H02M1/00 ,  G05F1/575 ,  H02M3/04 ,  H03F1/02

CPC classification number: H03F3/45237 ,  G05F1/461 ,  G05F1/561 ,  G05F1/575 ,  H02M1/00 ,  H02M3/04 ,  H02M7/04 ,  H02M2001/0009 ,  H02M2001/0045 ,  H02M2001/007 ,  H03F1/0238 ,  H03F3/45183 ,  H03F3/45273 ,  H03F2200/462 ,  H03F2203/45288

Abstract: One example includes a transconductor system. The system includes a first transconductance amplifier that generates a control current in response to a first input voltage. The system also includes a second transconductance amplifier that generates an output signal in response to a second input voltage. The system further includes an intermediate amplifier that generates a control voltage in response to the control current and a third input voltage. The control voltage can be provided to the first and second transconductance amplifiers to set a transconductance of each of the first and second transconductance amplifiers to be approximately equal.

公开(公告)号：US20190069087A1

公开(公告)日：2019-02-28

申请号：US16175907

申请日：2018-10-31

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Lars Risbo ,  Ryan Erik Lind ,  Jasjot Singh Chadha

IPC: H04R3/02 ,  H03F3/217 ,  H03F3/30 ,  H03F3/45 ,  H03F3/185 ,  H04R3/00

CPC classification number: H04R3/02 ,  H03F3/185 ,  H03F3/2173 ,  H03F3/3022 ,  H03F3/45192 ,  H03F2200/03 ,  H03F2200/351 ,  H03F2200/411 ,  H04R3/00

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.

公开(公告)号：US09930452B2

公开(公告)日：2018-03-27

申请号：US15395290

申请日：2016-12-30

Applicant: TEXAS INSTRUMENTS INCORPORATED

Inventor： Lars Risbo ,  Ryan Erik Lind ,  Jasjot Singh Chadha

IPC: H04B15/00 ,  H04R3/02 ,  H03F3/217 ,  H03F3/185

CPC classification number: H04R3/02 ,  H03F3/185 ,  H03F3/2173 ,  H03F3/3022 ,  H03F3/45192 ,  H03F2200/03 ,  H03F2200/351 ,  H03F2200/411 ,  H04R3/00

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.