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A comment on the US lays out a road safety plan that will see cars 'talk' to each other. Parent comment

Re:the US lays out a road safety plan that will see cars 'ta... by mastercheif on Wednesday August 21, 2024 @10:11AM (#41310480)
To add on to this: We need to regulate the use of PWM modulation in external LEDs on vehicles. Too many manufacturers are using 120Hz - 200Hz modulation frequency which are easily detectable by the human eye when motion is involved. You'll know when you're looking at a car with PWM headlights when at night they look like they are blurring.

https://www.youtube.com/watch?v=m5JzxjWtFaY

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Re:the US lays out a road safety plan that will see cars 'ta... by Sohcahtoa82 on Wednesday August 21, 2024 @01:54PM (#41312560)
Why do they use PWM instead of simply passing less current?
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Re:the US lays out a road safety plan that will see cars 'ta... by aidenn0 on Wednesday August 21, 2024 @08:26PM (#41315526)
Cost. A PWM needs only one external component (a MOSFET), while a current regulator needs multiple.
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Re:the US lays out a road safety plan that will see cars 'ta... by Sohcahtoa82 on Wednesday August 21, 2024 @10:41PM (#41316308)
I admit my knowledge on electronics is pretty basic, but to reduce current, don't you just need a resistor?
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Re:the US lays out a road safety plan that will see cars 'ta... by aidenn0 on Monday August 26, 2024 @05:04PM (#41362163)
So a diode is a constant-voltage device. If you put a resistor in series and run a line voltage above the diode's voltage than the current will be limited by ohms law.

But, variable resistors that are rated for a lot of power (roughly half the power of the diodes at max brightness) will add to the BOM.

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