Electronics > Beginners
Please help me understand this circuit
<< < (5/5)
MarkF:

--- Quote from: Moriambar on January 27, 2019, 11:47:18 am ---
--- Quote from: MarkF on January 27, 2019, 07:32:08 am ---If you use a SPDT switch, you can control both the turn on time (via R1) and the turn off time (via R2).
Maybe start with R1=10K, R2=1K and C1=100nF.

   OR

Just add a resistor in parallel with the capacitor in your original circuit. 
You would need to keep in mind the series current when the switch is on if you do this.


--- End quote ---

thanks, the spdt switch was actually one of the original ideas, but I was trying to build it without it, something more "automatic" in order to have a temporary pushbutton instead of a proper switch.

Nice idea though

--- End quote ---

You do know they make momentary SPDT switches?
Example:
   https://www.mouser.com/ProductDetail/E-Switch/FS5700SPMT2B2M1QEH?qs=sGAEpiMZZMvxtGF7dlGNpp%252bW2sLS6zO28qxKefzNuxg%3d
GeorgeOfTheJungle:

--- Quote from: MarkF on January 27, 2019, 03:45:59 pm ---   uF == microF == 10-6

--- End quote ---
     µF == microF == 10-6
MarkF:

--- Quote from: GeorgeOfTheJungle on January 27, 2019, 08:10:52 pm ---
--- Quote from: MarkF on January 27, 2019, 03:45:59 pm ---   uF == microF == 10-6

--- End quote ---
     µF == microF == 10-6

--- End quote ---
Yes. But, trying not to use special characters.
Audioguru:
All the cheap Chinese LED flashlights that use 24 white LEDs have all the LEDs in parallel and they all look to be at the same brightness. Do they hire somebody to test them all and sort them into matched piles?
Richard Crowley:

--- Quote from: Audioguru on January 27, 2019, 08:39:28 pm ---All the cheap Chinese LED flashlights that use 24 white LEDs have all the LEDs in parallel and they all look to be at the same brightness. Do they hire somebody to test them all and sort them into matched piles?
--- End quote ---

1) Machines on the assembly line sort the dice into brightness "bins".  All semiconductors go through extensive testing on the line. LEDs are no exception.

2) Those dice only appear to be"matched" at the beginning of their brief life-span.  Watch a few videos from BigClive to see how well they fare over the longer term.
Navigation
Message Index
Previous page
There was an error while thanking
Thanking...

Go to full version
Powered by SMFPacks Advanced Attachments Uploader Mod