Not enough amps? $5 for the answer!
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- JonathanMC
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- Joined:Thu Nov 25, 2010 9:14 am
- Location:USA
I am finishing a N64P, but it has a big screen (8") which is making things difficult. It needs 12V, (it will NOT go lower than around 11V), but I only have 7.4V batteries. I searched for a LONG time to find a regulator but I found none. Then it was suggested use a 5v to 12V regulator, feeding off the N64 regulator. So i did that, and of course, it doesn't work right!
Basically, I am trying to run the screen off of two regulators, and it doesn't seem to provide enough amps. When i turn the screen on the power goes down to 6V, the screen goes off, then the power goes back up. How can I power my screen? HELP!?!?
Ill give $5 to the person that gives me the right answer!
Basically, I am trying to run the screen off of two regulators, and it doesn't seem to provide enough amps. When i turn the screen on the power goes down to 6V, the screen goes off, then the power goes back up. How can I power my screen? HELP!?!?
Ill give $5 to the person that gives me the right answer!
- marshallh
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Re: Not enough amps? $5 for the answer!
Your problem is that you are trying to run the entire screen from a regulator that does at most 500mA @ 5v. It is already running the n64, it would make sense this would fail.
What you need to do is to build a switching boost converter to take your 7.4v straight from the battery and boost it to 12v.
http://www.national.com/mpf/LM/LM2587.html" onclick="window.open(this.href);return false;
There are many chips you can use to do this, most of them work the same way. There's a schematic for 12v in the datasheet. (Page 18)
Make sure you buy the 12v part number and its support circuitry.
What you need to do is to build a switching boost converter to take your 7.4v straight from the battery and boost it to 12v.
http://www.national.com/mpf/LM/LM2587.html" onclick="window.open(this.href);return false;
There are many chips you can use to do this, most of them work the same way. There's a schematic for 12v in the datasheet. (Page 18)
Make sure you buy the 12v part number and its support circuitry.
Re: Not enough amps? $5 for the answer!
You need this:
http://search.digikey.com/scripts/DkSea ... 587T-12-ND" onclick="window.open(this.href);return false;
Look at page 18 of the datasheet, and follow the specs they've listed there. That will let you input 7.4V (roughly) and output 12 at about 1 Amp/hour.
EDIT:
Dang, marshallh beat me to it.
http://search.digikey.com/scripts/DkSea ... 587T-12-ND" onclick="window.open(this.href);return false;
Look at page 18 of the datasheet, and follow the specs they've listed there. That will let you input 7.4V (roughly) and output 12 at about 1 Amp/hour.
EDIT:
Dang, marshallh beat me to it.
- JonathanMC
- Posts:145
- Joined:Thu Nov 25, 2010 9:14 am
- Location:USA
Re: Not enough amps? $5 for the answer!
Ok, thanks both of you, but I guess Marshallh "won" sice he answered first.
Okay, the diagram doesn't look like the picture on Digi-key, but I guess its the same?
What is the loopy line in the middle top?
What is thh symbol that looks like "play"?
Thanks to all!
Marshallh- can you PM me your Paypal so i can send you $5?
Okay, the diagram doesn't look like the picture on Digi-key, but I guess its the same?
What is the loopy line in the middle top?
What is thh symbol that looks like "play"?
Thanks to all!
Marshallh- can you PM me your Paypal so i can send you $5?
Re: Not enough amps? $5 for the answer!
Squiggly = L = Inductor = http://search.digikey.com/scripts/DkSea ... -1126-5-ND" onclick="window.open(this.href);return false;
Play = Schotky (Or someting like that) Diode = http://search.digikey.com/scripts/DkSea ... 5822GOS-ND" onclick="window.open(this.href);return false;
I trust you can find the right capacitors and resistor?
Play = Schotky (Or someting like that) Diode = http://search.digikey.com/scripts/DkSea ... 5822GOS-ND" onclick="window.open(this.href);return false;
I trust you can find the right capacitors and resistor?
- JonathanMC
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- Joined:Thu Nov 25, 2010 9:14 am
- Location:USA
Re: Not enough amps? $5 for the answer!
Cool thanks, that's all I need to know. I appreciate it!Snipeye wrote:Squiggly = L = Inductor = http://search.digikey.com/scripts/DkSea ... -1126-5-ND" onclick="window.open(this.href);return false;
Play = Schotky (Or someting like that) Diode = http://search.digikey.com/scripts/DkSea ... 5822GOS-ND" onclick="window.open(this.href);return false;
I trust you can find the right capacitors and resistor?
- JonathanMC
- Posts:145
- Joined:Thu Nov 25, 2010 9:14 am
- Location:USA
Re: Not enough amps? $5 for the answer!
OK, I wired it up. At first it wasn't working. Then I rearranged some things and got the same voltage that was coming in. After that I changed the wiring to the regulator and now i am getting about 18V, which is too much. Any advise?
- JonathanMC
- Posts:145
- Joined:Thu Nov 25, 2010 9:14 am
- Location:USA
Not enough amps? $5 for the answer!
Ok, it's been awhile, but I still need some help. Like I said before, if I wire it the way the diagram says, I don get any increase in voltage. If I wire it what seems to be backwards, then I get 18V. I tested the 18V and when there is a load on the regulator it shuts off, then on, then off, etc. The unregulated voltage isn't enough, so it doesn't work either.... WHY????!!!!?!?!?
Re: Not enough amps? $5 for the answer!
Pictures, pictures, pictures. If we have more details (such as pictures) we can see what's wrong and help.
- JonathanMC
- Posts:145
- Joined:Thu Nov 25, 2010 9:14 am
- Location:USA
Not enough amps? $5 for the answer!
I will if this next thing I ordered doesnt work. Marshallh sent me a link to something else that should work. Thanks though.