公开(公告)号：US09351352B2

公开(公告)日：2016-05-24

申请号：US14452335

申请日：2014-08-05

Applicant: Linear Technology Corporation

Inventor： Keith D. Szolusha

IPC: H05B33/08

CPC classification number: H05B33/08 ,  H05B33/0815 ,  H05B33/0818 ,  Y02B20/346

Abstract: A converter has a boost portion and a buck portion. The boost portion supplies a boosted voltage and includes a first inductor having a first end coupled to the input terminal, a first switch coupled to a second end of the first inductor to charge the first inductor when the first switch is in its on-state, and a first capacitor for being charged to the boosted voltage. The buck portion supplies an output voltage to a load that is less than the boosted voltage and includes a second inductor in series with the load, and a second switch in series with the second inductor and the load to charge the second inductor during an on-state of the second switch. A single controller IC receives feedback signals and controls the switches to have the same duty cycle to achieve a regulated load current or voltage with low EMI.

Abstract translation: A转换器具有升压部分和降压部分。 升压部分提供升压电压并且包括具有耦合到输入端子的第一端的第一电感器，耦合到第一电感器的第二端以在第一开关处于其导通状态时对第一电感器充电的第一开关， 以及用于被充电到升压电压的第一电容器。 降压部分将输出电压提供给小于升压电压的负载，并且包括与负载串联的第二电感器，以及与第二电感器和负载串联的第二开关，以在通电期间对第二电感器充电， 第二个开关的状态。 单个控制器IC接收反馈信号并控制开关具有相同的占空比，以实现具有低EMI的稳压负载电流或电压。

公开(公告)号：US20150145439A1

公开(公告)日：2015-05-28

申请号：US14264518

申请日：2014-04-29

Applicant: Linear Technology Corporation

Inventor： Keith D. Szolusha ,  Joshua W. Caldwell ,  Bryan Legates

IPC: H05B33/08

CPC classification number: H05B33/0851 ,  H05B33/0809 ,  H05B33/0815 ,  H05B33/0818 ,  H05B41/28 ,  Y02B20/346 ,  Y02B20/347

Abstract: In a method for controlling a current regulator for dimming an LED load, a dimming signal has a duty cycle that controls the LED ON-time and LED OFF time at a fixed frequency. The regulator is controlled by the dimming signal to only supply current to the LED load during the LED ON-time. The regulator includes an inductor. The inductor current at the end of an ON-time is detected and its value is stored. During the OFF-time, the inductor is pre-charged to the current level matching the stored value, while the regulator's feedback loop is frozen during the OFF-time to not change its feedback control signal. Upon the next ON-time, the regulator begins supplying current to the LED load with the pre-charged inductor current, so there is no initial decrease in the delivered LED current. Therefore, the current pulse magnitudes are constant even with very low duty cycles.

Abstract translation: 在用于控制用于调光LED负载的电流调节器的方法中，调光信号具有以固定频率控制LED接通时间和LED熄灭时间的占空比。 调光器由调光信号控制，以便在LED接通时间期间仅向LED负载提供电流。 调节器包括电感器。 检测接通时间结束时的电感电流，并存储其值。 在关断期间，电感器预充电到与存储值匹配的电流电平，而稳压器的反馈环路在关断时间冻结，不改变其反馈控制信号。 在下一个导通时间后，调节器开始向预充电电感电流的LED负载供电，因此LED电流的传送没有初始减少。 因此，即使在非常低的占空比下，当前脉冲幅度也是恒定的。

公开(公告)号：US20140111110A1

公开(公告)日：2014-04-24

申请号：US13656559

申请日：2012-10-19

Applicant: LINEAR TECHNOLOGY CORPORATION

Inventor： Xin Qi ,  Eric S. Young ,  Keith D. Szolusha

IPC: H05B37/02

CPC classification number: H05B33/0845 ,  H05B33/0818 ,  Y02B20/347

Abstract: A technique to eliminate perceptible flickering by LEDs being dimmed by PWM pulses is disclosed. A controllable oscillator controls a switching frequency of a converter for supplying a regulated current or regulated voltage. The converter controls a first switch at a switching frequency. A varying second signal level is generated by a spread spectrum control (SSC) circuit for controlling the oscillator to vary the switching frequency during operation. A PWM dimming circuit generates a string of PWM pulses that control a switch in series with the LEDs. The SSC circuit is synchronized with the PWM pulses to generate the same second signal level at a start of each PWM pulse, such that the switching frequency of the converter is forced to be substantially the same at the start of each PWM pulse while the pulse widths are constant. The repeating driving current waveform eliminates perceptible flicker by the LEDs.

Abstract translation: 公开了消除由PWM脉冲调光的LED的可感知闪烁的技术。 可控振荡器控制用于提供调节电流或调节电压的转换器的开关频率。 转换器以开关频率控制第一开关。 变化的第二信号电平由扩频控制（SSC）电路产生，用于控制振荡器在操作期间改变开关频率。 PWM调光电路产生一串PWM脉冲，控制与LED串联的开关。 SSC电路与PWM脉冲同步，以在每个PWM脉冲的起始处产生相同的第二信号电平，使得转换器的开关频率在每个PWM脉冲开始时被强制为基本相同，而脉冲宽度 是恒定的 重复的驱动电流波形消除了LED的可察觉的闪烁。

公开(公告)号：US10368410B2

公开(公告)日：2019-07-30

申请号：US13656559

申请日：2012-10-19

Applicant: Linear Technology Corporation

Inventor： Xin Qi ,  Eric S. Young ,  Keith D. Szolusha

IPC: H05B33/00 ,  H05B33/08

Abstract: A technique to eliminate perceptible flickering by LEDs being dimmed by PWM pulses is disclosed. A controllable oscillator controls a switching frequency of a converter for supplying a regulated current or regulated voltage. The converter controls a first switch at a switching frequency. A varying second signal level is generated by a spread spectrum control (SSC) circuit for controlling the oscillator to vary the switching frequency during operation. A PWM dimming circuit generates a string of PWM pulses that control a switch in series with the LEDs. The SSC circuit is synchronized with the PWM pulses to generate the same second signal level at a start of each PWM pulse, such that the switching frequency of the converter is forced to be substantially the same at the start of each PWM pulse while the pulse widths are constant. The repeating driving current waveform eliminates perceptible flicker by the LEDs.

公开(公告)号：US08975831B1

公开(公告)日：2015-03-10

申请号：US14264477

申请日：2014-04-29

Applicant: Linear Technology Corporation

Inventor： Keith D. Szolusha ,  Joshua W. Caldwell

IPC: G05F1/00 ,  H05B33/08

CPC classification number: H05B33/0851 ,  H05B33/0809 ,  H05B33/0815 ,  H05B33/0818 ,  H05B41/28 ,  Y02B20/346 ,  Y02B20/347

Abstract: In a method for controlling a current regulator for dimming an LED load, an adjustable delay circuit generates a delayed second dimming signal from an original first dimming signal. The second dimming signal has a duty cycle that controls the LED ON-time and LED OFF time at a fixed frequency. An ON-time pulse of the first dimming signal starts a pre-charging of the regulator's inductor to approximately the inductor current previously detected at the end of the previous ON-time of the LEDs. The pre-charging ends at the leading edge of the delayed ON-time pulse of the second dimming signal. The second dimming signal controls the regulator to only supply current to the LED load during the LED ON-time. The delay time is adjusted by a feedback loop. Therefore, the current pulse magnitudes applied to the LED load are constant at every duty cycle even with very low duty cycles.

Abstract translation: 在用于控制用于调光LED负载的电流调节器的方法中，可调节延迟电路从原始第一调光信号产生延迟的第二调光信号。 第二个调光信号具有占空比，以固定的频率控制LED导通时间和LED关断时间。 第一调光信号的导通时间脉冲开始将调节器电感器的预充电约为先前在LED的接通时间结束时检测到的电感器电流。 预充电在第二调光信号的延迟接通时间脉冲的前沿结束。 第二个调光信号控制调节器，以便在LED接通时间期间仅向LED负载提供电流。 延迟时间由反馈回路调整。 因此，即使在非常低的占空比下，施加到LED负载的当前脉冲幅度在每个占空比下也是恒定的。

公开(公告)号：US09178427B1

公开(公告)日：2015-11-03

申请号：US14638868

申请日：2015-03-04

Applicant: Linear Technology Corporation

Inventor： Keith D. Szolusha

IPC: H05B37/02 ,  H02M3/158 ,  H05B33/08

CPC classification number: H02M3/158 ,  H02M3/005 ,  H02M3/1582 ,  H02M3/1588 ,  H02M2001/0003 ,  H05B33/0815 ,  Y02B70/1466

Abstract: A converter generates an output voltage differential across a floating load, such as a string of LEDs. The converter receives an input voltage Vin from a power supply, and the floating output voltage differential may be greater than or less than Vin. The converter uses a first switch and first inductor in a boost mode type configuration, and uses a second switch and second inductor in a buck mode type configuration. The inductors have a common node. The first inductor has another end coupled to ground, and the other end of the second inductor is coupled to the load. Both inductors charge and discharge together depending on the conductivities of the switches. One end of the load will be approximately zero volts, while the other end will be at a negative voltage VEE. The two inductors smooth input current/voltage ripple and output current/voltage ripple, resulting in low EMI.

Abstract translation: A转换器在浮动负载（如一串LED）上产生输出电压差。 转换器从电源接收输入电压Vin，浮动输出电压差可以大于或小于Vin。 转换器采用升压模式配置中的第一开关和第一电感器，并以降压模式配置使用第二开关和第二电感器。 电感器有一个公共节点。 第一电感器具有耦合到地的另一端，并且第二电感器的另一端耦合到负载。 两个电感器根据开关的电导率一起充电和放电。 负载的一端约为零伏，而另一端将处于负电压VEE。 两个电感器平滑输入电流/电压纹波和输出电流/电压纹波，导致低EMI。

公开(公告)号：US20150289325A1

公开(公告)日：2015-10-08

申请号：US14452335

申请日：2014-08-05

Applicant: Linear Technology Corporation

Inventor： Keith D. Szolusha

IPC: H05B33/08

CPC classification number: H05B33/08 ,  H05B33/0815 ,  H05B33/0818 ,  Y02B20/346

Abstract: A converter has a boost portion and a buck portion. The boost portion supplies a boosted voltage and includes a first inductor having a first end coupled to the input terminal, a first switch coupled to a second end of the first inductor to charge the first inductor when the first switch is in its on-state, and a first capacitor for being charged to the boosted voltage. The buck portion supplies an output voltage to a load that is less than the boosted voltage and includes a second inductor in series with the load, and a second switch in series with the second inductor and the load to charge the second inductor during an on-state of the second switch. A single controller IC receives feedback signals and controls the switches to have the same duty cycle to achieve a regulated load current or voltage with low EMI.

Abstract translation: A转换器具有升压部分和降压部分。 升压部分提供升压电压并且包括具有耦合到输入端子的第一端的第一电感器，耦合到第一电感器的第二端以在第一开关处于其导通状态时对第一电感器充电的第一开关， 以及用于被充电到升压电压的第一电容器。 降压部分将输出电压提供给小于升压电压的负载，并且包括与负载串联的第二电感器，以及与第二电感器和负载串联的第二开关，以在通电期间对第二电感器充电， 第二个开关的状态。 单个控制器IC接收反馈信号并控制开关具有相同的占空比，以实现具有低EMI的稳压负载电流或电压。

公开(公告)号：US09078317B1

公开(公告)日：2015-07-07

申请号：US14332830

申请日：2014-07-16

Applicant: Linear Technology Corporation

Inventor： Keith D. Szolusha

IPC: H05B37/02 ,  H05B33/08

CPC classification number: H05B33/0815

Abstract: An LED driver uses a positive-to-floating boost converter topology to generate a negative voltage −Vee relative to ground. The converter receives an input voltage. Vin from a power supply. One end of an output inductor is coupled to ground, and the other end of the inductor is coupled between a highside switch and a low side switch. The bottom terminal of the lowside switch generates −Vee. The anode end of an LED string is coupled to Vin and the cathode end is coupled to −Vee. The converter detects the LED current and regulates the switching duty cycle so that the LED current is equal to a target current. This is more efficient than coupling the anode end of an LED string to ground and the cathode end to −Vee. A conventional buck controller IC may be used.

Abstract translation: LED驱动器使用正浮置升压转换器拓扑来产生相对于地的负电压。 转换器接收输入电压。 Vin从电源。 输出电感器的一端耦合到地，并且电感器的另一端耦合在高侧开关和低侧开关之间。 低端开关的底端产生-Vee。 LED串的阳极端耦合到Vin，阴极端耦合到-Vee。 转换器检测LED电流并调节开关占空比，使LED电流等于目标电流。 这比将LED串的阳极端耦合到地和阴极端更有效。 可以使用传统的降压控制器IC。

公开(公告)号：US09072147B2

公开(公告)日：2015-06-30

申请号：US14264518

申请日：2014-04-29

Applicant: Linear Technology Corporation

Inventor： Keith D. Szolusha ,  Joshua W. Caldwell ,  Bryan Legates

IPC: H05B33/08 ,  H05B41/28

CPC classification number: H05B33/0851 ,  H05B33/0809 ,  H05B33/0815 ,  H05B33/0818 ,  H05B41/28 ,  Y02B20/346 ,  Y02B20/347

Abstract: In a method for controlling a current regulator for dimming an LED load, a dimming signal has a duty cycle that controls the LED ON-time and LED OFF time at a fixed frequency. The regulator is controlled by the dimming signal to only supply current to the LED load during the LED ON-time. The regulator includes an inductor. The inductor current at the end of an ON-time is detected and its value is stored. During the OFF-time, the inductor is pre-charged to the current level matching the stored value, while the regulator's feedback loop is frozen during the OFF-time to not change its feedback control signal. Upon the next ON-time, the regulator begins supplying current to the LED load with the pre-charged inductor current, so there is no initial decrease in the delivered LED current. Therefore, the current pulse magnitudes are constant even with very low duty cycles.

Abstract translation: 在用于控制用于调光LED负载的电流调节器的方法中，调光信号具有以固定频率控制LED接通时间和LED关闭时间的占空比。 调光器由调光信号控制，以便在LED接通时间期间仅向LED负载提供电流。 调节器包括电感器。 检测接通时间结束时的电感电流，并存储其值。 在关断期间，电感器预充电到与存储值匹配的电流电平，而稳压器的反馈环路在关断时间冻结，不改变其反馈控制信号。 在下一个导通时间后，调节器开始向预充电电感电流的LED负载供电，因此LED电流的传送没有初始减少。 因此，即使在非常低的占空比下，当前脉冲幅度也是恒定的。