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Looking for help with a flash circuit
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Looking for help with a flash circuit

by DavidRangde on Sat Aug 24, 2019 6:58 am

I'm looking for help designing a circuit that can slowly ramp up the brightness of a blue LED whilst charging a small flashbulb as you'd find in a disposable camera please. Once it peaks, flash, then stay from the beginning. I can also saw it being possible to run a stepped version where more than one LEDs are lit in sequence using capacitors, but I'm unsure I'm new to electronics and don't know enough to figure this out. Is this possible to do with only simple components (ie avoiding IC chips if possible) Thanks for any help!

DavidRangde
 
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Re: Looking for help with a flash circuit

by westfw on Sun Aug 25, 2019 1:42 am

Disposable camera flashes are a bit problematic because they’re designed to run off a 1.5v AA battery at pretty substantial current, while most electronics (including BLE leds) will want something more like 5v.

Have you seen http://repairfaq.cis.upenn.edu/sam/strbfil.htm ?

Be careful. A charged disposable camera flash holds a near-fatal dose of energy. Even following a discharge through the tube, the capacitor will hold enough voltage to make a substantial mark on a screwdriver, or give you a nasty shock...
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Re: Looking for help with a flash circuit

by adafruit_support_bill on Sun Aug 25, 2019 8:31 am

Even following a discharge through the tube, the capacitor will hold enough voltage to make a substantial mark on a screwdriver, or give you a nasty shock...

A fully charged one will blow the tip right off the screwdriver, DAMHIKT ;-)

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Re: Looking for help with a flash circuit

by DavidRangde on Sun Aug 25, 2019 5:17 pm

DavidRangde wrote:I'm looking for help designing a circuit that can slowly ramp up the brightness of a blue LED whilst charging a small flashbulb as you'd find in a disposable camera please. Once it peaks, flash, then stay from https://discord.software/ FetLife vshare
the beginning. I can also saw it being possible to run a stepped version where more than one LEDs are lit in sequence using capacitors, but I'm unsure I'm new to electronics and don't know enough to figure this out. Is this possible to do with only simple components (ie avoiding IC chips if possible) Thanks for any help!



my issue got solved!!

DavidRangde
 
Posts: 2
Joined: Sat Aug 24, 2019 6:32 am

Please be positive and constructive with your questions and comments.