公开(公告)号：US09735671B2

公开(公告)日：2017-08-15

申请号：US14280539

申请日：2014-05-16

Applicant: Cirrus Logic, Inc.

Inventor： John L. Melanson ,  Ramin Zanbaghi ,  Jieyeon Choi ,  Firas Azrai ,  Rahul Singh ,  Siddharth Maru

IPC: H05B33/08 ,  H02M3/07 ,  H02M1/08 ,  H03K17/64 ,  H02M3/335 ,  H02M1/00

CPC classification number: H02M3/07 ,  H02M1/08 ,  H02M3/335 ,  H02M2001/0006 ,  H03K17/64 ,  H05B33/0815 ,  H05B33/0845

Abstract: A bipolar junction transistor (BJT) may be used to generate a supply voltage for operating a controller, such as a lighting controller for a LED-based light bulb. A base of the BJT may receive current generated from the supply voltage to control operation of the BJT. Although the base of the BJT would be at a lower voltage than the emitter, a base drive circuit may be coupled between the emitter and the base of the BJT to increase the voltage. As one example, the base drive circuit may be a charge pump. In another example, the BJT may function as its own charge pump. In yet another example, a positive and a negative base current of the BJT may be independently controlled to regulate an output supply voltage VDD from the BJT.

公开(公告)号：US09722620B1

公开(公告)日：2017-08-01

申请号：US15338818

申请日：2016-10-31

Applicant: Cirrus Logic, Inc.

Inventor： Ramin Zanbaghi ,  Yousof Mortazavi ,  John L. Melanson ,  Aaron Brennan

IPC: H03M1/06 ,  G10L19/00

CPC classification number: H03M1/0602 ,  G10L19/00 ,  H03M1/1004 ,  H03M1/1038 ,  H03M1/1042 ,  H03M1/188 ,  H03M1/60

Abstract: The overall performance of a dual-path ADC system may be improved by using a VCO-based ADC for small-amplitude signals and employing non-linear cancelation to remove nonlinearities in signals output by the VCO-based ADC. In particular, VCO-based dual-path ADC systems of this disclosure may be configured to receive a first digital signal from a first ADC and a second digital signal from a second ADC, wherein the second digital signal is more non-linear than the first digital signal. The dual-path systems may also be configured to determine one or more non-linear coefficients of the second digital signal based, at least in part, on processing of the first and second digital signals. The dual-path systems may be further configured to modify the second digital signal based, at least in part, on the determined one or more non-linear coefficients to generate a more linear second digital signal.

公开(公告)号：US09603206B2

公开(公告)日：2017-03-21

申请号：US14696212

申请日：2015-04-24

Applicant: Cirrus Logic, Inc.

Inventor： Ramin Zanbaghi

IPC: H05B33/08 ,  H03K17/60 ,  H02M1/00

CPC classification number: H05B33/0815 ,  H02M1/00 ,  H02M1/08 ,  H03K17/602 ,  H05B33/0845 ,  H05B33/0887 ,  Y02B20/347

Abstract: A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as a converter in LED-based light bulbs. A closed-loop control system may be implemented with the power stage to monitor a tail current of the BJT. The closed-loop control system may include a first comparator for monitoring a base voltage while a pull-down current source is coupled to the base of the BJT. Additionally, a second comparator may be included for monitoring the base voltage after the pull-down current source is decoupled from the base of the BJT. The delay time for turning off the BJT may be determined by monitoring output from the first and second comparators. The forward base current applied to the base of the BJT may be adjusted based on the determined delay time to reduce the delay time and thus reduce excess power dissipation by the BJT.

公开(公告)号：US09503027B2

公开(公告)日：2016-11-22

申请号：US14524867

申请日：2014-10-27

Applicant: Cirrus Logic, Inc.

Inventor： Ramin Zanbaghi

IPC: H03F3/185 ,  H03F3/217 ,  H03K7/08 ,  H03F1/02 ,  H03F1/30

CPC classification number: H03F1/0277 ,  H03F1/305 ,  H03F3/185 ,  H03F3/2171 ,  H03F3/2175 ,  H03F2200/03 ,  H03F2200/129 ,  H03F2200/321 ,  H03F2200/324 ,  H03F2200/351 ,  H03F2200/432 ,  H03K7/08

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：US20160255686A1

公开(公告)日：2016-09-01

申请号：US14696212

申请日：2015-04-24

Applicant: Cirrus Logic, Inc.

Inventor： Ramin Zanbaghi

IPC: H05B33/08 ,  H03K17/60

CPC classification number: H05B33/0815 ,  H02M1/00 ,  H02M1/08 ,  H03K17/602 ,  H05B33/0845 ,  H05B33/0887 ,  Y02B20/347

Abstract: A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as a converter in LED-based light bulbs. A closed-loop control system may be implemented with the power stage to monitor a tail current of the BJT. The closed-loop control system may include a first comparator for monitoring a base voltage while a pull-down current source is coupled to the base of the BJT. Additionally, a second comparator may be included for monitoring the base voltage after the pull-down current source is decoupled from the base of the BJT. The delay time for turning off the BJT may be determined by monitoring output from the first and second comparators. The forward base current applied to the base of the BJT may be adjusted based on the determined delay time to reduce the delay time and thus reduce excess power dissipation by the BJT.

Abstract translation: 双极结型晶体管（BJT）可用于功率级DC-DC转换器，例如基于LED的灯泡中的转换器。 可以用功率级来实现闭环控制系统以监测BJT的尾流。 闭环控制系统可以包括用于监视基极电压的第一比较器，而下拉电流源耦合到BJT的基极。 此外，可以包括第二比较器，用于在下拉电流源与BJT的基极分离之后监视基极电压。 关闭BJT的延迟时间可以通过监视来自第一和第二比较器的输出来确定。 可以基于确定的延迟时间来调整施加到BJT的基极的正向基极电流，以减少延迟时间，从而减少BJT的功率消耗。

公开(公告)号：US20150028764A1

公开(公告)日：2015-01-29

申请号：US14444087

申请日：2014-07-28

Applicant: Cirrus Logic, Inc.

Inventor： Siddharth Maru ,  John L. Melanson ,  Rahul Singh ,  Eric King ,  Thirumalai Rengachari ,  Ramin Zanbaghi ,  Arnab Kumar Dutta

IPC: H03K4/48 ,  H05B33/08

CPC classification number: H03K4/48 ,  H05B33/0815 ,  H05B37/02 ,  Y02B20/347

Abstract: A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as for LED-based light bulbs. The BJT may be switched on and off from a controller coupled to two terminals of the BJT. Through the two terminals, the control IC may dynamically adjust a reverse recovery time period of the BJT. The reverse recovery time period may be adjusted by changing an amount of base charge that accumulates on the BJT. Additional, the reverse recovery may be controlled through the use of a reverse base current source applied to the BJT after beginning switching off the BJT.

Abstract translation: 双极结型晶体管（BJT）可用于功率级DC-DC转换器，例如用于基于LED的灯泡。 BJT可以从耦合到BJT的两个端子的控制器接通和断开。 通过两个端子，控制IC可以动态地调整BJT的反向恢复时间段。 可以通过改变在BJT上积累的基本电荷的量来调整反向恢复时间段。 此外，可以通过在开始关闭BJT之后使用施加到BJT的反向基极电流源来控制反向恢复。

公开(公告)号：US09504106B2

公开(公告)日：2016-11-22

申请号：US14341984

申请日：2014-07-28

Applicant: Cirrus Logic, Inc.

Inventor： John L. Melanson ,  Thirumalai Rengachari ,  Siddharth Maru ,  Ramin Zanbaghi ,  Firas Azrai ,  Rahul Singh

IPC: H05B37/02 ,  H05B33/08 ,  H02M3/156

CPC classification number: H05B33/0815 ,  H02M3/156 ,  H05B33/0845 ,  H05B37/02

Abstract: A turn-off transition time period, also referred to as a reverse recovery time period, may be compensated for by a controller of a power stage including a bipolar junction transistor (BJT). The reverse recovery time period may be measured in one switching cycle and a subsequent switching cycle may include compensations based on the measured reverse recovery time period. That is the switching on and off of the BJT may be compensated to obtain a desired average output current to a load. When the reverse recovery time period is known, an error in the peak current obtained due to the reverse recovery time period may be calculated. The calculated error may be used to offset the target peak current for controlling the switching of the BJT to begin a turn-off transition of the BJT earlier in a switching cycle and thus reduce error in peak current at the BJT.

Abstract translation: 还可以通过包括双极结型晶体管（BJT）的功率级的控制器补偿关断转换时间段（也称为反向恢复时间周期）。 可以在一个开关周期内测量反向恢复时间段，并且随后的开关周期可以包括基于所测量的反向恢复时间段的补偿。 也就是说，可以补偿BJT的接通和断开以获得期望的负载平均输出电流。 当已知反向恢复时间周期时，可以计算由于反向恢复时间段而获得的峰值电流的误差。 计算出的误差可用于偏移目标峰值电流，以控制BJT的开关，以便在开关周期中较早地开始BJT的关断转换，从而减小BJT的峰值电流误差。

公开(公告)号：US20160255685A1

公开(公告)日：2016-09-01

申请号：US14634716

申请日：2015-02-27

Applicant: Cirrus Logic, Inc.

Inventor： John L. Melanson ,  Ramin Zanbaghi ,  Thirumalai Rengachari ,  Prashanth Drakshapalli ,  Rahul Singh ,  Arnab Kumar Dutta

IPC: H05B33/08

CPC classification number: H05B33/0815 ,  H02M3/335 ,  H05B33/0845 ,  H05B33/0887 ,  H05B37/02

Abstract: A bipolar junction transistor (BJT) may be used in a power stage DC-to-DC converter, such as a converter in LED-based light bulbs. The power stage may be operated by a controller to maintain a desired current output to the LED load. The controller may operate the power stage by monitoring a start and end of a reverse recovery time of the BJT. Information regarding the start and end of the reverse recovery time may be used in the control of the power stage to improve efficiency of the power stage.

Abstract translation: 双极结型晶体管（BJT）可用于功率级DC-DC转换器，例如基于LED的灯泡中的转换器。 功率级可以由控制器操作以保持对LED负载的期望的电流输出。 控制器可以通过监视BJT的反向恢复时间的开始和结束来操作功率级。 关于反向恢复时间的开始和结束的信息可以用于功率级的控制，以提高功率级的效率。

公开(公告)号：US20140339995A1

公开(公告)日：2014-11-20

申请号：US14280474

申请日：2014-05-16

Applicant: Cirrus Logic, Inc.

Inventor： Ramin Zanbaghi ,  John L. Melanson ,  Jieyeon Choi

IPC: H05B33/08 ,  H02M3/158

CPC classification number: H05B33/0815 ,  H02M3/158 ,  H02M2001/0009 ,  H05B33/0845 ,  Y02B20/346

Abstract: A power stage for light emitting diode (LED)-based light bulbs may include a bipolar junction transistor (BJT). The base of BJT switch may be biased externally and the operation of the BJT may be through a single pin to the emitter of the BJT. A controller integrated circuit (IC) may control the power stage through the main BJT's emitter pin in an emitter-controlled BJT-based power stage. The emitter-controlled BJT-based power stage may replace the conventional buck-boost power stage topology. For example, the controller may activate and deactivate a switch coupling the BJT's emitter to ground. A power supply for the controller IC may be charged from a reverse recovery of charge from the BJT, and the reverse recovery controlled by the controller IC.

Abstract translation: 基于发光二极管（LED）的灯泡的功率级可以包括双极结型晶体管（BJT）。 BJT开关的基极可能被外部偏置，并且BJT的操作可能通过BJT的发射极的单个引脚。 控制器集成电路（IC）可以通过发射极控制的基于BJT的功率级中的主BJ​​T发射极引脚来控制功率级。 基于发射极控制的基于BJT的功率级可以取代传统的降压 - 升压功率级拓扑。 例如，控制器可以激活和去激活将BJT的发射极耦合到地的开关。 用于控制器IC的电源可以从BJT的反向恢复电荷和由控制器IC控制的反向恢复来充电。

公开(公告)号：US20140333205A1

公开(公告)日：2014-11-13

申请号：US14276535

申请日：2014-05-13

Applicant: Cirrus Logic, Inc.

Inventor： Michael A. Kost ,  Eric J. King ,  John L. Melanson ,  Kan Wang ,  Ramin Zanbaghi

IPC: H02M5/458 ,  H05B33/08

CPC classification number: H02M5/458 ,  H05B33/0815 ,  H05B33/0887

Abstract: An electronic transformer stabilization circuit includes a detection circuit and a reactive load. The detection circuit may be configured to receive a transformer output or a transformer signal derived from the transformer output. The detection circuit may determine whether the transformer that generated the transformer output is an electronic transformer. The determination may be made based on the presence of absence of high frequency components in the transformer output. Responsive to determining that an electronic transformer generated the transformer output, the stabilization circuit may operate a switch to connect the reactive load across an output of the transformer. The reactive load may include an inductor and may be configured to draw a stabilization current from the transformer. The stabilization current may ensure that the total current drawn from the transformer exceeds an oscillation current required to maintain reliable operation of the electronic transformer.

Abstract translation: 电子变压器稳定电路包括检测电路和无功负载。 检测电路可以被配置为接收从变压器输出导出的变压器输出或变压器信号。 检测电路可以确定产生变压器输出的变压器是电子变压器。 可以基于变压器输出中是否存在高频分量进行确定。 响应于确定电子变压器产生变压器输出，稳定电路可以操作开关以连接变压器输出端上的无功负载。 无功负载可以包括电感器，并且可以被配置成从变压器抽出稳定电流。 稳定电流可以确保从变压器抽出的总电流超过维持电子变压器可靠运行所需的振荡电流。