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。

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：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。