[Ronja] Testing switching time of an LED

[Pramod yaduvanshi]

Dear Deepak ,
Then you are wrong person trying out your hand on ronja !! use a simple
signal generator or fucntion generator to test the LED !!
Which city are you in ? Superflux LED are available in India
PK Yaduvanshi


On 21/03/2008, Deepak Mishra <xask.linus at gmail.com> wrote:
>
> Sorry man , but I do not know how to generate a pulse !
> What signal source do I use ?
> I have no practical experience in electronics
>
> Regards,
> Deepak
>
> On 21/03/2008, Arun Krishnan <arunk at speedpost.net> wrote:
> >
> > Hi Deepak,
> >
> > I don't think a 555 can clock to the 10Mhz you'll need to test your LED
> > at.
> >
> > But I'm thinking you can measure the rise and fall time just by a single
> > pulse and a CRO that has enough resolution.
> >
> >
> > Regards,
> > Arun
> >
> >
> > ----- Original message -----
> > From: "Deepak Mishra" <xask.linus at gmail.com>
> > To: "Twibright Ronja" <ronja at lists.pointless.net>
> >
> > Date: Fri, 21 Mar 2008 20:00:19 +0530
> > Subject: Re: [Ronja] Testing switching time of an LED
> >
> > Thanks ,
> > I had this basic idea in mind that I must apply a fast input square wave
> > signal to the led and check the output using a scope on the photo diode.
> >
> > But the basic problem is I am such a new bie that I am not sure if i
> > should
> > connect
> > the photo diode directly to the oscilloscope and with resistor in series
> > or
> > what ??
> >
> > And how do i generate a square wave signal of the desired frequency ?
> > I have heard of the 555 timer, do I have to use the breadboard ?
> >
> > I good with software, but not so good at hard ware, I hope you get the
> > idea
> > ?
> >
> > Thanks anyway!
> > Cheers,
> > Deepak
> >
> >
> > On 21/03/2008, Arun Krishnan <arunk at speedpost.net> wrote:
> > >
> > > Hi Deepak,
> > >
> > > You'll need to hook up the LED to a simple square wave generator and
> > use
> > > a fast photodiode connected to a CRO to measure how fast it is
> > > switching. There are other methods where you could program something
> > > like a microcontroller to measure it, but the easier way would be to
> > use
> > > a CRO.
> > >
> > > Regards,
> > > Arun
> > >
> > >
> > >
> > > ----- Original message -----
> > > From: "Deepak Mishra" <xask.linus at gmail.com>
> > > To: "Twibright Ronja" <ronja at lists.pointless.net>
> > > Date: Fri, 21 Mar 2008 19:13:44 +0530
> > > Subject: [Ronja] Testing switching time of an LED
> > >
> > > Hi all !,
> > >
> > > As always, I am having trouble find the LED HPWT-xxxx-xxxx.
> > > So I am going to test some LED manufactured in my country (India)
> > easily
> > > available at low costs.
> > >
> > > I mainly want to test the rise/fall time of the LED and its not in the
> > > datasheet.
> > >
> > > I am an electronics newbie, so could somebody point me to an
> > electronic
> > > circuit and a way to measure
> > > the rise and fall times of the LED ?
> > >
> > > Cheers,
> > > Deepak
> > >
> > >
> > > --
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> > >
> >
> >
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>
>
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