公开(公告)号：US20170047895A1

公开(公告)日：2017-02-16

申请号：US15336995

申请日：2016-10-28

Applicant: Cirrus Logic, Inc.

Inventor： Ramin ZANBAGHI

IPC: H03F1/02 ,  H03F3/185 ,  H03F3/217 ,  H03F1/30

Abstract: An integrated circuit may have two signal paths: an open-loop modulator (which may comprise a digital-input Class-D amplifier) and a closed-loop modulator (which may comprise an analog-input Class-D amplifier). A control subsystem may be capable of selecting either of the open-loop modulator or the closed-loop modulator as a selected path based on one or more characteristics (e.g., signal magnitude) of an input audio signal. For example, for higher-magnitude signals, the closed-loop modulator may be selected while the open-loop modulator may be selected for lower-magnitude signals. In some instances, when the open-loop modulator is selected as the selected path, the closed-loop modulator may power off, which may reduce power consumption. In addition, one or more techniques may be applied to reduce or eliminate user-perceptible audio artifacts caused by switching between the open-loop modulator and the closed-loop modulator, and vice versa.

Abstract translation: 集成电路可以具有两个信号路径：开环调制器（其可以包括数字输入D类放大器）和闭环调制器（其可以包括模拟输入D类放大器）。 控制子系统可以基于输入音频信号的一个或多个特性（例如，信号幅度）来选择开环调制器或闭环调制器中的任一个作为选择的路径。 例如，对于较高幅度的信号，可以选择闭环调制器，同时为低电平信号选择开环调制器。 在一些情况下，当选择开环调制器作为选择的路径时，闭环调制器可以断电，这可能降低功耗。 此外，可以应用一种或多种技术来减少或消除由开环调制器和闭环调制器之间的切换引起的用户可感知的音频伪像，反之亦然。

公开(公告)号：US20140312797A1

公开(公告)日：2014-10-23

申请号：US14158445

申请日：2014-01-17

Applicant: Cirrus Logic, Inc.

Inventor： Ramin ZANBAGHI ,  Arnab Kumar DUTTA ,  Firas AZRAI

IPC: H05B33/08

CPC classification number: H05B33/0872 ,  H02M7/5383 ,  H05B33/0815 ,  H05B33/0866 ,  Y02B20/347 ,  Y02B70/1441

Abstract: A self-oscillating resonator (SOR) may be used to control current through light emitting diodes (LEDs). The SOR may be started and stopped by a controller coupled to a transistor switch in the SOR. The controller may output a control signal that starts and stops the SOR by coupling a supply voltage or a ground to a base of the transistor switch in the SOR. Additional control over the current output to the LEDs may be gained through a resistive DAC coupled to the SOR and duty cycling the SOR.

Abstract translation: 自振荡谐振器（SOR）可用于控制通过发光二极管（LED）的电流。 SOR可以由耦合到SOR中的晶体管开关的控制器启动和停止。 控制器可以通过在SOR中将电源电压或接地耦合到晶体管开关的基极来输出启动和停止SOR的控制信号。 可以通过耦合到SOR的电阻式DAC和SOR负载来获得对LED的电流输出的额外控制。