Re: Simple Circuit Design

On Thu, 02 Mar 2006 16:05:46 -0600, John Fields
<jfields@xxxxxxxxxxxxxxxxxxxxx> wrote:

On 2 Mar 2006 09:39:15 -0800, "artbinct" <bauera@xxxxxxx> wrote:

In simple terms, all I really want to do is control a bright white LED
using (2) 2032 coin cell batteries (I don't have a lot of room) and a
remotely located magnetic switch (NO or NC) so that the LED turns ON
when the magnet is moved away from the switch and the LED turns OFF
when the magnet is moved near the switch. The challenge for me is have
the LED turn OFF after roughly 2-3 minutes after being turned on.
Thanks.

---
Sorry, hit the TX button by mistake on the last one.

OK. AIUI, (if we use the analogy of a window actuated switch) with
the window shut, the LED will be off. If the window is raised the
LED will come on and will stay on for a few minutes and then go off
even if the window stays open, but if the window is closed before
the few minutes goes by, the LED will go off as soon as the window
is closed.

On top of that, because of your battery constraints, you'd like to
have the circuit draw zero or close to zero power when the window is
closed or when the LED goes off if the window is still open but the
circuit times out, right?

How much room have you got for circuitry?

--
John Fields
Professional Circuit Designer
.