Alt-BEAM Archive
Message #09258
To: "'beam@sgiblab.sgi.com'" beam@sgiblab.sgi.com
From: Wilf Rigter Wilf.Rigter@powertech.bc.ca
Date: Sun, 16 Jan 2000 12:00:25 -0800
Subject: [alt-beam] Re: D1
PUT THIS SIGN OVER YOUR WORK SPACE:
"ALWAYS TERMINATE UNUSED CMOS INPUTS!"
GRIN
WILF
> -----Original Message-----
> From: Bumper314@aol.com [SMTP:Bumper314@aol.com]
> Sent: Saturday, January 15, 2000 8:49 PM
> To: beam@sgiblab.sgi.com
> Subject: Re: D1
>
> In a message dated 1/15/00 9:44:51 PM Mountain Standard Time,
> Bumper314@aol.com writes:
>
> > Oh....i was just trying variety...most of my LEDs I tried were red, they
>
> have
> >
> > the lowest voltage drop correct? I have had this thing running on one
> of
> > those Solarbotics SMD red LEDs for about 2 hours now, but dim and like
> I
> > said
> > in the other e-mail, I cant hardly move it. I have it in a box with the
>
> > solar
> > cell down, and im in a low light room, but even moving the box makes
> the
> > thing freak out. I know its not due to any loose connections since the
> 5
> > other times it was doing this and on the breadboard....I just dont know
>
> But that's not to say I don't want this new circuit. I appreciate the time
>
> you are spending on this. I am curious if I should run all the remaining
> input/outputs of the 74HC14 to ground or V+. They are just floating right
> now
> and I think that might be causing this weird behavior ...just a thought
> though
9259 Sun, 16 Jan 2000 15:01:53 -0500 (EST) [alt-beam] Re: Lotus 1, by Sparky. New Beam Page beam@sgiblab.sgi.com jester96beam@iname.com Whenever I try to go to that page, my whole computer freezes! It always has. It's the only page that my computer doesn't like. Anyone have any idea why this may happen? Is there anything 'different' about that page?
Chris
---- you wrote:
> Hey, I noticed that your robot made it onto Arrick robotic's robot show-off
> gallery! Nice work! Check it out at:
>
> http://www.robotics.com/robomenu/
>
>
> dennison
>
> Hey Guys!
> I finally have a web page to show off my walker.
> (THANKS TO BRUCE !!! )
> check it out and tell me what you think!
>
> http://www3.telus.net/rfws/beam/sparky/index.html
>
> -Sparky
>
>
---------------------------------------------------
Get free personalized email at http://www.iname.com
9260 Sun, 16 Jan 2000 12:54:21 -0800 [alt-beam] Re: D1 "'beam@sgiblab.sgi.com'" Wilf Rigter
Ok,ok here it is:
THE LEDPUMP
This simple circuit combines two dynamite circuits. An even simpler SIMD1
and a LED charge pump/flasher.
Despite the LEDPUMP's apparent simplicity, it is a major improvements over
original the D1 and PUMMER circuits.
The SIMD1 is a very simple D1 type SE which charges during the day and turns
on a flashing LED at night. In addition to the solar cell and capacitor (or
NiCd), it uses just 1 diode for isolation to prevent discharging a fully
charged cap through the solar cell in the dark and another diode to hold
off a flasher/threshold detector which turns on at night. It just doesn't
get much simpler!
The second part of the design shown is the simplest of all LEDPUMP versions
and is used to drive LEDs from a single 1.5V battery (SBolt notice) ie. for
the AQUAGUARD circuit, but works perfectly well from a solar charger and
supercap. In the attached circuit, I used a coin super cap charged to 2V to
flash a LED once a second for 8hrs and it's still going. To optimize
performance, you must use a premium high brightness high efficiency LED. The
simplicity of design was emphasized to make it easy to freeform the circuit
into jewelry etc.
You can also use this design at much higher frequency (100kHz) to turn the
LED on continuously, I used 1M/100pf for the oscillator and 0.33 for the
chargepump cap. If you use a higher voltage solar cell and 5V super cap, the
single LED can be replaced with two LEDs in series. I have several other
versions which use one or two more components and are more efficient than
the basic LEDPUMP design shown. This includes replacing the diode in series
with the LED with a synchronous rectifier (2N3904 and 100K resistor) or
simply adding a 10K resistor in parallel with the diode to reduce the diode
forward voltage drop and precharge the cap to 0V before the active pulse to
increase brightness and efficiency.
The basic LEDPUMP (LED, CAP, DIODE) design can be used with low voltage
microcontrollers, and other micropower applications etc to increase LED
driving voltage. Although it may not be obvious, since the LEDPUMP seems
like such a simple circuit, it is potentially my most important contribution
to date. Remember were you saw it first.
enjoy
wilf
<>
> -----Original Message-----
> From: Bumper314@aol.com [SMTP:Bumper314@aol.com]
> Sent: Saturday, January 15, 2000 8:49 PM
> To: beam@sgiblab.sgi.com
> Subject: Re: D1
>
> In a message dated 1/15/00 9:44:51 PM Mountain Standard Time,
> Bumper314@aol.com writes:
>
>
> But that's not to say I don't want this new circuit. I appreciate the time
>
> you are spending on this.
>
[Wilf Rigter] thanks!
Attachment: LEDPUMP2.gif
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