Need more current

[sniper007]

Hi!

I'd like to connect 3 equal LED in parallel instead one in this circuit. What need to change ( probably C and R) and what value ?

note: asking for 220V


**broken link removed**




Regards,

Jurif

 

[mneary]

Connect three LEDs in series and you won't need to make any other changes.

 

[bychon]

Brilliant answer! I was assuming parallel was the only way to figure this. Let sniper say if series will work. He might not have thought of it...like me.

By the way, what is a BSD?

 

[Reloadron]

Brilliant answer! I was assuming parallel was the only way to figure this. Let sniper say if series will work. He might not have thought of it...like me.

By the way, what is a BSD?

BSD = Berkley Software Distribution which did not come from Dr. Timothy Leary's department.

Ron

 

[mneary]

It's a derivative of UNIX. See www.bsd.org.

 

[Hero999]

Here's how I'd do it.

EDIT:
What's the forward voltage of the LEDs?

If you don't know that, what colour are they?

I've just realised that this probably isn't a good idea if they're white, blue or violet, since the maximum reverse voltage listed on the datasheet is normally only 5V, and the forward voltage of these colours is normally 3.5V, giving 7V in total. Having said that, I've connected a 12V battery to an LED backwards before and no harm was done.

 

[Ubergeek63]

Hi!

I'd like to connect 3 equal LED in parallel instead one in this circuit. What need to change ( probably C and R) and what value ?

note: asking for 220V


**broken link removed**




Regards,

Jurif

replace D1 with a rectifier bridge to instantly double the current drive...

 

[sniper007]

Thanks guys, thanks for quick replays.

I was talking again with my friend who need this circuit and told me that he'd like to change this circuit to this way that can connect one LED with 30mA current. Now output of this circuit is 10mA. So what is the best way to get more current ?

 

[Ubergeek63]

Thanks guys, thanks for quick replays.

I was talking again with my friend who need this circuit and told me that he'd like to change this circuit to this way that can connect one LED with 30mA current. Now output of this circuit is 10mA. So what is the best way to get more current ?

full wave bridge doubles the current... increasing the capacitor value will increase it some more

 

[sniper007]

you mean to change diode with full wave bridge ?

 

[MrAl]

Hi there,


Yes, using a full wave bridge provides for a better utilization of the parts, in that you get more current for the buck.

Also, if you dont like that you can use two LEDs in series, and that in anti parallel with two more LEDs in series, for a total of four LEDs and that doesnt require a diode.