Power supplies
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Posts: 46,084
I've been planning on using a surplus computer power supply to suplly
power to my motor and circuits while I'm developing them.
Unfortunately, I can't seem to figure out the connections. The web
pages I found show color coding that just doesn't seem to match at
all, and I can only find +5 volt connections with my meter.
Everything else seems to have VERY (.03 volts, etc) low power.
Does anyone ( actually, I'm pretty sure someone here would....) know
where I can find this out?
I'm using an Astec model atx202-3525
The closest I could find was:
http://www.phm.lu/documentation/connectors/PCPower.asp
power to my motor and circuits while I'm developing them.
Unfortunately, I can't seem to figure out the connections. The web
pages I found show color coding that just doesn't seem to match at
all, and I can only find +5 volt connections with my meter.
Everything else seems to have VERY (.03 volts, etc) low power.
Does anyone ( actually, I'm pretty sure someone here would....) know
where I can find this out?
I'm using an Astec model atx202-3525
The closest I could find was:
http://www.phm.lu/documentation/connectors/PCPower.asp
Comments
minimum load on the +5 volt output....some that we tested go into a "hiccup"
mode, where the supply turns on for a burst, then shuts off in a repeating
cycle. Try loading the +5V with 3 or 4 amps (power resistor), then explore
the other outputs with your DVM. The 12V output will probably read high
until it is also loaded. We have several switching supplies operating Stamp
projects, and found it necessary to keep a load resistor across the supply
because most of the Stamp stuff is low current drain.
Good luck,
Ray McArthur
> I've been planning on using a surplus computer power supply to suplly
> power to my motor and circuits while I'm developing them.
> Unfortunately, I can't seem to figure out the connections. The web
> pages I found show color coding that just doesn't seem to match at
> all, and I can only find +5 volt connections with my meter.
> Everything else seems to have VERY (.03 volts, etc) low power.
> Does anyone ( actually, I'm pretty sure someone here would....) know
> where I can find this out?
> I'm using an Astec model atx202-3525
>
is always supplying +5 at a low level. When the "power switch" is
pressed on the PC the supply then turns on all the other supplies. One
of the pins has to be properly biased to let anything happen. My spec
for the ATX power supply is at work so I can't tell you with great
certainty which one it is. Do a web search on ATX power supply and you
will come up with all you need to know. Be careful, there is some
hazardous energy available on the outputs of these supplies. Fusing
might be a good idea.
On Wed, 20 Sep 2000 00:20:23 -0000 jtrauma@b... writes:
> I've been planning on using a surplus computer power supply to suplly
>
> power to my motor and circuits while I'm developing them.
> Unfortunately, I can't seem to figure out the connections. The web
> pages I found show color coding that just doesn't seem to match at
> all, and I can only find +5 volt connections with my meter.
> Everything else seems to have VERY (.03 volts, etc) low power.
> Does anyone ( actually, I'm pretty sure someone here would....) know
>
> where I can find this out?
> I'm using an Astec model atx202-3525
> The closest I could find was:
> http://www.phm.lu/documentation/connectors/PCPower.asp
>
>
>
>
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a robot? Will the 5v part of the supply work for running not only
the BS2 but also some servo motors? Would i need to make any
modifications or just plug everything into it. I just dont want to
fry everything.
Jay
the power supply for the BOE, where I can plug use the wall supply or a
battery. As I understand, I shouldn't just connect the battery or wall
supply directly to the stamp, but need some circuitry.
any suggestions? I'd like to build it myself if it's not too complicated and
I'm looking for experience in this area
bob
For the Stamp, if you want to use one directly, you need a REGULATED
power supply. If it doesn't say regulated, run away as fast as you can.
Take for example, a power supply that is UNREGULATED 5 Volts at 1 Amp.
What this means is that the output Voltage will be about 5 Volts at one
Amp of current. However, there are internal losses within the wall
wart. So, when you put on a load of less than one Amp, the Voltage
available at the output of the power supply will rise. In the case of a
12 Volt unregulated power supply, it may go as high as 15 Volts.
Look at your local Hamfest for used cheap ones ($1 or more). Or Radio
Shack or Digikey or Jameco.
I have a BOE version, and it has an on board regulator. It runs off of
the wall wart or the 9 Volt battery.
NOTE: The data sheets for the 5 Volt 3 terminal regulators say that you
have to put bypassing at the pins of the device or it will tend to
oscillate. While it may not be under your current test conditions,
things change. I just go ahead and put 10 uF and a 0.1 uF right close
to the input and the output pins (both) and run with it.
Final thing, a 3 terminal regulator generally needs about 3 to 3.5 Volts
of overhead. This means that you need to feed a 5 Volt regulator with
8+ Volts so that it has enough room to regulate. They have a minimum
Voltage drop across them that influences the overhead requirements also.
There are versions that require less overhead, but I don't remember the
numbers.
Original Message
From: eclecticrr@A... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=7U1xtBWgAh8viAo7kOANY6n-qfuZLSPYR_BjSnfidYeDqeee2tLP-RdGuJiaLNvU9dslBnsXJ4GG-ZUD]eclecticrr@A...[/url
Sent: Tuesday, February 25, 2003 2:15 PM
To: basicstamps@yahoogroups.com
Subject: [noparse][[/noparse]basicstamps] power supplies
I need a power source for a one of the stamp OEM boards. I'd like to be
like
the power supply for the BOE, where I can plug use the wall supply or a
battery. As I understand, I shouldn't just connect the battery or wall
supply directly to the stamp, but need some circuitry.
any suggestions? I'd like to build it myself if it's not too
complicated and
I'm looking for experience in this area
bob
To UNSUBSCRIBE, just send mail to:
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The standard is a 7805. Properly heat sinked these are good to at least
1 amp (much more than you need for the Stamp). The "catch" is that the
more voltage you put in, the more heat the chip burns off. Also, you
need a good deal more than 5V in to get 5V out (say around 7 or 8V). The
7805 is pin compatible with a 2940-5. Same heat problem, but you can run
them at just over 5V in and get 5V out.
If you have high voltages, you can replace the 7805 with a TI switching
module which is pretty much pin compatible with a 7805 but is physically
larger.
We make a kit with a 7805 for this purpose. The bare board is usable
with the other compatible regulators. See
http://www.al-williams.com/ps1.htm
You can also use a 78L05 (looks like a transistor) up to about 100mA.
Other than that, they are the same as a 7805.
Assuming your wall wart is DC, you simply connect the input to the 7805.
If you are worried about noise, put a filter capacitor across the input.
Most 7805s want a .1uF cap near the output terminals. That's it. Say
9-12V in and 5V regulated out.
If you do a search on 7805 on Google, you should find a wealth of info.
They make other 78xx regulators for other voltages (e.g., 7812 is a 12V
regulator). The 79xx are negative regulators (7905 is a -5V regulator).
Al Williams
AWC
* NEW: PAK-VIa - Read PS/2 keyboards or mice -- double the buffer, lower
current consumption.
http://www.al-williams.com/awce/pak6.htm
>
Original Message
> From: eclecticrr@A... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=0TVBcEkdoygSgOCZdxd53dmFEBUQGttLvj9PngnSGVne4XkxcTqTzn4zoSgYyrZ91dnZM6WHM3AF]eclecticrr@A...[/url
> Sent: Tuesday, February 25, 2003 1:15 PM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] power supplies
>
>
> I need a power source for a one of the stamp OEM boards. I'd
> like to be like
> the power supply for the BOE, where I can plug use the wall
> supply or a
> battery. As I understand, I shouldn't just connect the
> battery or wall
> supply directly to the stamp, but need some circuitry.
>
> any suggestions? I'd like to build it myself if it's not too
> complicated and
> I'm looking for experience in this area
>
> bob
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the
> Subject and Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
>
>
>
internal regulator which can well be used if it is just the stamp
itself that needs to be powerded.
I made a little programming board which consists of no more than a
ZIF-socket (the most important part), a reset button, a power on LED
(low power) and a piece of ribbon cable. I connect a battery or wall-
wart (can be unregulated but should be well filtered) to Vin and Vss
and an LED between Vdd and Vss.
Regards
Adrian
weeks ago, but couldn't you use the unregulated power input pin on the
stamp?
Giacomo Ferrari
Date: Tue, 25 Feb 2003 14:08:30 -0600
From: "Al Williams" <alw@a...>
Subject: RE: power supplies
What you need is a regulator. There are plenty of ways to go.
The standard is a 7805. Properly heat sinked these are good to at least
1 amp (much more than you need for the Stamp). The "catch" is that the
more voltage you put in, the more heat the chip burns off. Also, you
need a good deal more than 5V in to get 5V out (say around 7 or 8V). The
7805 is pin compatible with a 2940-5. Same heat problem, but you can run
them at just over 5V in and get 5V out.
If you have high voltages, you can replace the 7805 with a TI switching
module which is pretty much pin compatible with a 7805 but is physically
larger.
We make a kit with a 7805 for this purpose. The bare board is usable
with the other compatible regulators. See
http://www.al-williams.com/ps1.htm
You can also use a 78L05 (looks like a transistor) up to about 100mA.
Other than that, they are the same as a 7805.
Assuming your wall wart is DC, you simply connect the input to the 7805.
If you are worried about noise, put a
filter capacitor across the input.
Most 7805s want a .1uF cap near the output terminals. That's it. Say
9-12V in and 5V regulated out.
If you do a search on 7805 on Google, you should find a wealth of info.
They make other 78xx regulators for other voltages (e.g., 7812 is a 12V
regulator). The 79xx are negative regulators (7905 is a -5V regulator).
Al Williams
AWC
* NEW: PAK-VIa - Read PS/2 keyboards or mice -- double the buffer, lower
current consumption.
http://www.al-williams.com/awce/pak6.htm
>
Original Message
> From: eclecticrr@A... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=yE22UN_wBmhAtADfDfS4NCipg7lPc9-9szCu2WF7HDYdHwDp54T-1uXhNGcx5IbTYeaCT5rgGSGKgt4]eclecticrr@A...[/url
> Sent: Tuesday, February 25, 2003 1:15 PM
> To: basicstamps@yahoogroups.com
> Subject: [noparse][[/noparse]basicstamps] power supplies
>
>
> I need a power source for a one of the stamp OEM boards. I'd
> like to be like
> the power supply for the BOE, where I can plug use the wall
> supply or a
> battery. As I understand, I shouldn't just connect the
> battery or wall
> supply directly to the stamp, but need some circuitry.
>
> any suggestions? I'd like to build it myself if it's not too
> complicated and
> I'm looking for experience in this area
>
> bob
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the
> Subject and Body of the message will be ignored.
>
>
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/
>
>
>
>
thanks for all your advice
bob