--- In , "smitty505000" <smitty505000@y...>
wrote: > rstofer,
>
> Thanks for the info! It works perfect! I have 70 LED's 7 sets on 7
> pins wired in 2 series 5 parallel and she works like a charm. Take a > look on my page to see it.
> http://home.cfl.rr.com/smittyshobbies/r2d2.htm
> Thanks,
> Smitty
>
> --- In , "rtstofer" <rstofer@p...> wrote:
> >
> > Think about putting 2 LEDs in series and 5 parallel strings. So, > > the dropping resistor for each string is
probably 5V - 0.2V
> > (transistor) - 2.4V (1.2Vf per LED) / 0.02A or 120 Ohms. So, you > > need 5 strings each consisting of 2 LEDs in
series with a 120 Ohm > > resistor.
> >
> > Connect the resistor to +5 then through the LEDs and on to the
> > collector of the transistor. Connect the emitter to ground.
> >
> > Now, since the collector current will be 5 * 0.02A or 0.1A and the > > transistor gain is probably about 100 you
only need 0.1 / 100 base > > current of 100 uA. Assuming the port can pull
to +4V and the base- > > emitter drop is 0.6V we have 3.4V and 0.0001A
or 34K for the base > > resistor. Choose, say, 10k. So, connect a 10K
resistor from the > > I/O pin to the base. Check to see that the
transistor is fully
> > saturated (0.2V give or take from collector to emitter) and reduce > > the base resistor if necessary.
> >
> > If the port can drive 0.01A then the lower limit of the base
> > resistor is +5V - 0.6V (base emitter drop) / 0.01A or 440 Ohms.
> >
> >
> >
> > --- In , "smitty505000" <smitty505000@y...> > > wrote:
> > > --- In , "Dave Mucha" <davemucha@j...>
> > wrote:
> > > > --- In , "smitty505000"
> > <smitty505000@y...>
> > > > wrote:
> > > > > Hey guys,
> > > > >
> > > > > Do I need a transistor to drive say 10 LED's on
one
> output
> > > pin?
> > > > > Its going to be like 220ma. If so what kind of
transistor?
> > > > >
> > > > > Thanks,
> > > > > Smitty
> > > >
> > > >
> > > > pn2222
> > > >
> > > > 1 amp
> > > >
> > > > TO-92 case
> > > >
> > > > digi-key PN2222-ND 30 cents
> > >
> > > Thanks so much! I can get them from my favorite
> > > place "www.jameco.com" for 5 cents...lol
> > > Do I just hook it up with the base on the pic pin and the
> > collector
> > > to +5 and emitter to the led?
> > >
> > > Thanks for the help,
> > > Smitty
Reply by smitty505000●November 16, 20032003-11-16
rstofer,
Thanks for the info! It works perfect! I have 70 LED's 7 sets on 7
pins wired in 2 series 5 parallel and she works like a charm. Take a
look on my page to see it. http://home.cfl.rr.com/smittyshobbies/r2d2.htm
Thanks,
Smitty
--- In , "rtstofer" <rstofer@p...> wrote: >
> Think about putting 2 LEDs in series and 5 parallel strings. So,
> the dropping resistor for each string is probably 5V - 0.2V
> (transistor) - 2.4V (1.2Vf per LED) / 0.02A or 120 Ohms. So, you
> need 5 strings each consisting of 2 LEDs in series with a 120 Ohm
> resistor.
>
> Connect the resistor to +5 then through the LEDs and on to the
> collector of the transistor. Connect the emitter to ground.
>
> Now, since the collector current will be 5 * 0.02A or 0.1A and the
> transistor gain is probably about 100 you only need 0.1 / 100 base
> current of 100 uA. Assuming the port can pull to +4V and the base-
> emitter drop is 0.6V we have 3.4V and 0.0001A or 34K for the base
> resistor. Choose, say, 10k. So, connect a 10K resistor from the
> I/O pin to the base. Check to see that the transistor is fully
> saturated (0.2V give or take from collector to emitter) and reduce
> the base resistor if necessary.
>
> If the port can drive 0.01A then the lower limit of the base
> resistor is +5V - 0.6V (base emitter drop) / 0.01A or 440 Ohms.
>
> --- In , "smitty505000" <smitty505000@y...>
> wrote:
> > --- In , "Dave Mucha" <davemucha@j...>
> wrote:
> > > --- In , "smitty505000"
> <smitty505000@y...>
> > > wrote:
> > > > Hey guys,
> > > >
> > > > Do I need a transistor to drive say 10 LED's on one output > > pin?
> > > > Its going to be like 220ma. If so what kind of
transistor?
> > > >
> > > > Thanks,
> > > > Smitty
> > >
> > >
> > > pn2222
> > >
> > > 1 amp
> > >
> > > TO-92 case
> > >
> > > digi-key PN2222-ND 30 cents
> >
> > Thanks so much! I can get them from my favorite
> > place "www.jameco.com" for 5 cents...lol
> > Do I just hook it up with the base on the pic pin and the
> collector
> > to +5 and emitter to the led?
> >
> > Thanks for the help,
> > Smitty
Reply by John Remington●November 10, 20032003-11-10
www.glitchbuster.com, 12 for a buck.
Randy's great, ships right away, and you don't have a $25 minimum
and
$5 in shipping costs.
--- Dave Mucha <> wrote: > --- In , "smitty505000"
<smitty505000@y...>
> wrote:
> > Hey guys,
> >
> > Do I need a transistor to drive say 10 LED's on one output
pin?
>
> > Its going to be like 220ma. If so what kind of transistor?
> >
> > Thanks,
> > Smitty
> pn2222
>
> 1 amp
>
> TO-92 case
>
> digi-key PN2222-ND 30 cents
>
__________________________________
Reply by smitty505000●November 10, 20032003-11-10
Wow! Someones an electrical engineer. Thanks for the info. I think I
am going with the 2x5 series parallel. I have three boards to make,
two with 20 led's each and one with 69 led's. I am going to have one
pic16f628 drive the two with 20 and one pic for the board with 69
led's. The patterns are all different. If you are wondering what they
are for, they are logic displays for a full size R2D2 I am building.
Smitty
--- In , "rtstofer" <rstofer@p...> wrote: >
> Think about putting 2 LEDs in series and 5 parallel strings. So,
> the dropping resistor for each string is probably 5V - 0.2V
> (transistor) - 2.4V (1.2Vf per LED) / 0.02A or 120 Ohms. So, you
> need 5 strings each consisting of 2 LEDs in series with a 120 Ohm
> resistor.
>
> Connect the resistor to +5 then through the LEDs and on to the
> collector of the transistor. Connect the emitter to ground.
>
> Now, since the collector current will be 5 * 0.02A or 0.1A and the
> transistor gain is probably about 100 you only need 0.1 / 100 base
> current of 100 uA. Assuming the port can pull to +4V and the base-
> emitter drop is 0.6V we have 3.4V and 0.0001A or 34K for the base
> resistor. Choose, say, 10k. So, connect a 10K resistor from the
> I/O pin to the base. Check to see that the transistor is fully
> saturated (0.2V give or take from collector to emitter) and reduce
> the base resistor if necessary.
>
> If the port can drive 0.01A then the lower limit of the base
> resistor is +5V - 0.6V (base emitter drop) / 0.01A or 440 Ohms.
>
> --- In , "smitty505000" <smitty505000@y...>
> wrote:
> > --- In , "Dave Mucha" <davemucha@j...>
> wrote:
> > > --- In , "smitty505000"
> <smitty505000@y...>
> > > wrote:
> > > > Hey guys,
> > > >
> > > > Do I need a transistor to drive say 10 LED's on one output > > pin?
> > > > Its going to be like 220ma. If so what kind of
transistor?
> > > >
> > > > Thanks,
> > > > Smitty
> > >
> > >
> > > pn2222
> > >
> > > 1 amp
> > >
> > > TO-92 case
> > >
> > > digi-key PN2222-ND 30 cents
> >
> > Thanks so much! I can get them from my favorite
> > place "www.jameco.com" for 5 cents...lol
> > Do I just hook it up with the base on the pic pin and the
> collector
> > to +5 and emitter to the led?
> >
> > Thanks for the help,
> > Smitty
Reply by Dennis Clark●November 9, 20032003-11-09
D@#%! I'll have to remember this site!
DLC
Dave Mucha wrote: > --- In , "Phil" <phil1960us@y...>
wrote:
>
>>another good source of 2n2222s and TIP120s is
>
> www.glitchbuster.com.
>
>>He's a small guy but honest as the day is long, very prompt and has
>>great prices. the 2n2222's are 12/.98, TIP120s for .39 but more
>>importantly, his PICs are well below the big guys. no minimums and
>>he ships for a flat 1.85 first class (usa, only). Downside? he
>>doesn't have a fancy ordering system and you pay via paypal. I
>>always try to buy from him first. He's always asking for ideas on
>>what to stock.
>>
>>I have no affiliation other than I use him and want to see him
>
> remain
>
>>in biz...
>>
>>Phil
>
> you forgot to mention that he does not charge a lot for shipping.
>
> op's you did mention that, but it deserves repeating !
> Dave
>
> to unsubscribe, go to http://www.yahoogroups.com and follow the
instructions
>
> ">http://docs.yahoo.com/info/terms/
>
--
---------------------------------
* Dennis Clark http://www.techtoystoday.com *
* "Programming and Customizing the OOPic Microcontroller" Mcgraw-Hill
*
---------------------------------
Reply by Wouter van Ooijen●November 9, 20032003-11-09
> The more correct question is, did the European and World > business stay the
> same while your Netherlands business increased significantly? If so,
> you should be very pleased that your countrymen are buying from you.
In absolute figures E/W sales decreased significantly. This might be
caused by
- me changing from pricing in $ to pricing in Euro (but now both options
are available)
- changes in the $ to Euro exchange rate (which affects my prices)
- more competition (but www.phanderson.com, once a very good source,
stopped selling PICs!)
> If 'international' business is dropping
off, you either have
> more competition,
> or the customs hassles from increased border security are hurting you.
That might be the case for US, but not for most other countries. And I
doubt whether some bloke in the US who gets a mail packet from me is
actually aware of any change, except maybe an extra delay?
Wouter van Ooijen wrote:
... > BTW for some reason that I don't understand
my business one year ago was
> 1/3 Netherlands, 1/3 Europe, 1/3 rest of the world. Now it is more like
> 9/10 Netherlands.
> Wouter van Ooijen
The more correct question is, did the European and World business stay the
same while your Netherlands business increased significantly? If so,
you should be very pleased that your countrymen are buying from you.
If 'international' business is dropping off, you either have more
competition,
or the customs hassles from increased border security are hurting you.
R
Reply by Wouter van Ooijen●November 9, 20032003-11-09
> I wonder how many hobby > projects turned into commercial products?
My Wisp628 was originally a hobby project. ZPL (zero-pin bootloader) was
a hobby project too, I just sold a buch of development boards
(http://sss.voti.nl/dwarf) using this bootloader. The Jal compiler has
gone the other way: it is GPL now.
Looks like those good dutch boys are getting PIC-religion!
By the way, I like your selection. I'll have to point randy (mr
glitchbuster) to your site.
I think its great how this PIC stuff has a total grass-roots feel to
it. Microchip either lucked out or was brilliant in their strategy
of giving away the development environment. I wonder how many hobby
projects turned into commercial products?
Phil
--- In , "Wouter van Ooijen" <wouter@v...>
wrote: > > what do you charge to ship to seattle?? :(
>
> I am in the Netherlands, so my (fixed) shipping/handling cost increases > from E 3.00 (Netherlands, incl VAT) to E 5.00
(Europe, incl VAT), to US$ > 7.35 (World, excl. VAT).
>
> So having a shop like mine or glitchbuster's in every country will make > the hobby more affordable.
>
> BTW for some reason that I don't understand my business one year ago was > 1/3 Netherlands, 1/3 Europe, 1/3 rest of the
world. Now it is more like > 9/10 Netherlands.
>
> I do have a web interface for my shop, but I wrote it all myself. Some > say that shows.
>
> Wouter van Ooijen
>
> -- -------
> Van Ooijen Technische Informatica: www.voti.nl
> consultancy, development, PICmicro products
Reply by Dave Mucha●November 9, 20032003-11-09
--- In , "Phil" <phil1960us@y...> wrote: > another good source of 2n2222s and TIP120s is www.glitchbuster.com. > He's a small guy but honest as the day is
long, very prompt and has
> great prices. the 2n2222's are 12/.98, TIP120s for .39 but more
> importantly, his PICs are well below the big guys. no minimums and
> he ships for a flat 1.85 first class (usa, only). Downside? he
> doesn't have a fancy ordering system and you pay via paypal. I
> always try to buy from him first. He's always asking for ideas on
> what to stock.
>
> I have no affiliation other than I use him and want to see him remain > in biz...
>
> Phil
you forgot to mention that he does not charge a lot for shipping.
op's you did mention that, but it deserves repeating !
Dave