Correct zener diode and resistor
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I wish to implement a zener diode and led between the 9v power supply and
stamp to indicate when their is insufficient power to operate the stamp
properly. 3 questions:
1. at what voltage does the stamp stop operating as it should?
2. Would the following circuit light an led when the voltage falls
below the minimum required?
stamp - 9v + ---zener ---resistor --> stamp
3. which zener ?
4. resistor size?(is a resistor needed?)
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stamp to indicate when their is insufficient power to operate the stamp
properly. 3 questions:
1. at what voltage does the stamp stop operating as it should?
2. Would the following circuit light an led when the voltage falls
below the minimum required?
stamp - 9v + ---zener ---resistor --> stamp
3. which zener ?
4. resistor size?(is a resistor needed?)
_________________________________________________________________
Get your FREE download of MSN Explorer at http://explorer.msn.com/intl.asp.
Comments
4.5 v, 4.0 v?)?
>From: "JOHN BELL" <johnabell8@h...>
>Reply-To: basicstamps@yahoogroups.com
>To: basicstamps@yahoogroups.com
>Subject: [noparse][[/noparse]basicstamps] CORRECT ZENER DIODE AND RESISTOR
>Date: Sun, 09 Jun 2002 20:51:25 -0400
>
>I wish to implement a zener diode and led between the 9v power supply and
>stamp to indicate when their is insufficient power to operate the stamp
>properly. 3 questions:
>
>1. at what voltage does the stamp stop operating as it should?
>
>2. Would the following circuit light an led when the voltage falls
>below the minimum required?
>
> stamp - 9v + ---zener ---resistor --> stamp
>
>3. which zener ?
>
>4. resistor size?(is a resistor needed?)
>
>
>
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>Does anyone know at what voltage the Stamp stops operating properly(4.9 v,
>4.5 v, 4.0 v?)?
The reset circuit will trip if voltage drops to 4 volts - per the BS2 manual.
you could not really say it operates "properly" at that voltage,
because even a little bit of noise on the power supply can kick it
over the edge. I looked into it in some detail. If you want more
information, look here:
http://www.emesystems.com/BS2power.htm#Brownout
-- regards,
Tracy Allen
electronically monitored ecosystems
mailto:tracy@e...
http://www.emesystems.com
>Does anyone know at what voltage the Stamp stops operating properly(4.9 v,
>4.5 v, 4.0 v?)?
>
>
> >From: "JOHN BELL" <johnabell8@h...>
> >Reply-To: basicstamps@yahoogroups.com
> >To: basicstamps@yahoogroups.com
> >Subject: [noparse][[/noparse]basicstamps] CORRECT ZENER DIODE AND RESISTOR
> >Date: Sun, 09 Jun 2002 20:51:25 -0400
> >
> >I wish to implement a zener diode and led between the 9v power supply and
> >stamp to indicate when their is insufficient power to operate the stamp
> >properly. 3 questions:
> >
> >1. at what voltage does the stamp stop operating as it should?
> >
> >2. Would the following circuit light an led when the voltage falls
> >below the minimum required?
> >
> > stamp - 9v + ---zener ---resistor --> stamp
> >
> >3. which zener ?
> >
> >4. resistor size?(is a resistor needed?)
> >