//Display brightness//Each digit is on for a certain amount of microseconds//Then it is off until we have reached a total of 20ms for the function call//Let's assume each digit is on for 1000us//If each digit is on for 1ms, there are 4 digits, so the display is off for 16ms.//That's a ratio of 1ms to 16ms or 6.25% on time (PWM).//Let's define a variable called brightness that varies from://5000 blindingly bright (15.7mA current draw per digit)//2000 shockingly bright (11.4mA current draw per digit)//1000 pretty bright (5.9mA)//500 normal (3mA)//200 dim but readable (1.4mA)//50 dim but readable (0.56mA)//5 dim but readable (0.31mA)//1 dim but readable in dark (0.28mA)
You are saying its OK to pulse it at 100mA, my manufacturer says 30mA - hmm .Some TV remote controls use the internal resistance of the battery to limit the current through the IREDs, perhaps your running 192 LEDs from a couple of AA batteries is doing the same, how many LEDs are on at the same time ?Whichever, its bad practice.I run my 25mA rated LEDs at 18mA, and out of the last 25,000 LEDs since October, I have had only a couple of failures, so I stick to that current.I am pulsing the latest project ( 50% ) at 21 mA, still well inside of the recommended current.
I never said it was ok to pulse 100ma to anything,
I dont know how much current the LEDs Im using are running at,
I have read that you can safely double the safe limit when using a duty cycle less than 50%,
3) You think that any activity that doesn't immediately kill you is a safe activity.
QuoteI never said it was ok to pulse 100ma to anything,So have you measured what you supposed good LEDs are actually taking?There are two things getting damaged the LEDs and the electronics driving them.QuoteI dont know how much current the LEDs Im using are running at,So how do you know you are not damaging things?QuoteI have read that you can safely double the safe limit when using a duty cycle less than 50%,Safely doubling safe limits is an oxymoron. You can read all sorts of rubbish on the internet, it doesn't make it true.I can only tell you what will work 100% of the time for 100% of the people. I know this because I have spent my whole lave you measured what you supposed good LEDs are actually taking?There are two things gife designing reliable electronics. Any idiot can design unreliable electronics that works for maybe two or three years. Or that works and significantly shortens the life of parts.You can of course choose to ignore this, I can not stop you from being a total idiot. What I can do is point out that you are an idiot and point out why you are an idiot and why you are suffering from self delusions. Hopefully I can stop sensible people from following your idiotic total lack of logic.1) You do not have enough equipment or expertise to know if you are damaging a component.2) You appear not to know about peak current and power dissipation and how that relates to average current and average power dissipation.3) You think that any activity that doesn't immediately kill you is a safe activity.
What is true, is that you *want* to call me an idiot,
1) You do not have enough equipment or expertise to know if you are damaging a component.
The thing is that I would love to know wich rules/relations/equations does this guy use to get the current average just with the amount of time that the led is on and off, in this part of the code:
Engineering isn't about "you cannot do that", or "that's wrong". Engineering is about knowing why you cannot do it so you know when / where you can do it.People holding a simplistic view just lack common sense to understand that.