Hello expert,
Below is the customer requirement. How to understand this? Does it mean we should set the PWM dimming frequency no less than 1000Hz?
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Hello expert,
Below is the customer requirement. How to understand this? Does it mean we should set the PWM dimming frequency no less than 1000Hz?
Addition requirement as below: to keep the off time less than 0.00025s, for dimming frequency 1k we should limit the duty less than 75%. Am I right?
Hello Zhiyuan,
I would talk to the customer about clarification, but from the graph it seems in order to support the entire duty cycle range the PWM frequency needs to be a min of 1000 Hz. That is how I am interpreting it. It looks like it allows you to do variations in pwm duty cycle (%) depending on PWM frequency. That allows them to do dynamic adjustments. You really need to talk to the customer about getting clarification. I have never seen this type of plot.
-fhoude
The image is cut off on the bottom and the resolution isn't great. Can you give me a better image. I think you are probably write, but I can't confirm without the better image. Again, this is a customer requirement and I think you should get clarification from them. I haven't seen this plot before.
-fhoude
Hello fhoude,
ASSIST, CFD, IEEE1789 seems to be the flicker standard, customer just ask us to respect it.
Below is the picture with higher resolution
I am looking at this standard and this isn't an automotive standard. I have a copy of the IEEE 1789 standard and I am not seeing any of these plots. We regularly operate in some of the "forbidden areas" and I am not sure how our application pertains to this standard. I couldn't find anything in the standard that talks about drop amplitude or duration. Please go back to your customer and get clarification from them. I don't know how to help you.
-fhoude