Try this new SIMD1 / Solar Voltage Regulator for use with blinking LED
circuits (Pummers). It turns on when it gets dark, just like a D1 but the
output voltage is regulated to about 2V (depending on the reference LED Vf).


The SIMD1/solar regulator circuit draws no current during charging and when
turned on, it draws less than 100uA with a maximum 10ma output current. The
regulator provides constant LED brightness during the discharge and turns
off when 1F solar cap voltage drops below the LED turn on voltage. The LED
used for voltage reference in the solar regulator feedback loop and the LEDs
used for the flasher must be the same high efficiency type to match the
forward voltage specs. This circuit is ideal for supplying voltage to a
Bicore or 74HC14 LED flasher as shown below since it eliminates the LED
current limiting resistors and greatly reduces current consumption of the HC
flasher circuits. The PowerSaver Flasher uses capacitive output coupling to
produce brighter shorter flashes and has a much lower average current drain
than standard bicore or 74HC14 flashers. The PS Flasher with one LED circuit
(2 LEDs)runs all night from a 1F cap charged to 5.5V. Up to 12 LEDs can be
controlled with one 74HC14 flasher and probably would run for 2 hours from a
full charge. Use a range of timing resistors between 1M and 4.7M for each
oscillator to give a random light show appearance.

One interesting alternative is to substitute a 5V NiCad (4 cell) battery for
the 1F supercap which to increase the storage capacity many fold for use
with flag waver motors, pendulums, etc. With higher load current, the 100K
resistor may be replaced with 20K for up to 50mA output current. The
quiescent current of the regulator remains very low and is proportional to
the load current for high efficiency operation during discharge.

regards

wilf

<<D1_SOLARREG.gif>> <<STDFLASHER.gif>> <<PSFLASHER.gif>>

> -----Original Message-----
> From: Max Inggal [SMTP:Tacoman101@...]
> Sent: Monday, April 24, 2000 9:46 AM
> To: beam@egroups.com
> Subject: [beam] Re: Need help with the SIMD1
>
> Ok thank you wilf I got the SimD1 to work. Works like
> a charm. Takes 3 or so minutes to charge and then
> jump into a closet and BAM! The LED turns on. But
> with every solution comes another problem. I tried
> hooking a suspended bicore with 2 LEDs to the SIMD1.
> But for some unknown reason to me it works for a sec
> but then on one LED stays on constantly. At first I
> thought it was the bicore but it works fine on a
> battery but when hooked to the SIMD1, nothing. THe
> hooked all the neg points of the bicore to ground and
> the Postive point to the output of the inverter on the
> SIMD1. If you know whats going on please get back to me.
>
>