Using a picoPSU: tired of the problems. Please help.

[Amiga1992]

The PSU it had is burned. I teted it.

To sum up: if i plug it to the Amiga, it will not power up after flickingthe switch.
If i plug it to the Amiga ane THEN i plug the power to the picopsu, it will work fine if the switch was then on

Maybe a temp switch will fix this. I will buy one tomorrow.

[thgill]

This is starting to sound like your 12v brick might be the culprit.

Possibly its not capable of supplying the current necessary to keep the pico running when something more than a very small load is placed on it. Especially since it does it with both pico's.

[Amiga1992]

But it works fine if I do as I said (set switch to on then plug dc cable on picopsu). I tested it for a bunch of minutes and noticed no problem

[_psy]

so this sums onto first post, try without the switch...

[Amiga1992]

As I said I did try without the switch, but it still makes no sense. I tried another rocker switch, same result. Today I will try with a temporary switch.

[Allen1]

Originally Posted by Akira

The AC adapter came with the thing. It's some generic AC adapter, says it outputs 12-14V, 5.00-4.28A (TYP 12V 5.0A).
EPS Inc. Model: F10603-C. 60W AC Adapter

The picoPSU is a 120W model, both of them are. The only thing common to all this setup is the AC Adapter. Now I feel scared something might have broke into my two Amigas, but I have no regular power supply to test them with Will have to try and nab one on eBay or something. I wish I knew someone locally with an Amiga!

Hi there Akira,

If 12v is the normal voltage input for the picapsu, is it possible that you could borrow a (fully charged) car or electric bike 12v battery or something along those lines to use in place of the power brick? If you could, then add a 5 amp fuse as protection and make sure the polarity is ok when you connect it. This would let you know if its the power brick that's causing the issue (or not) and at least eliminate one of the possible sources of the problem.

Sometimes a power source like your brick can have dry solder joints around component legs which make for unreliable operation as contact is lost between the components and the rest of the circuit. Another problem is when a capacitor starts to leak and causes similar problems like it did in my laptop supply.

The car battery idea is OK as there is more than enough Ampage but its amazing how much damage to your clothing can occur if you get any acid on them, try for a sealed lead acid battery as used in electric bikes and the likes if you can.

If you do give that a go, and it worked ok then you have nothing to lose in opening up your power brick and taking a look at the components and solder joints and hopefully a quick resolder may cure the problem.

[_psy]

sometimes electronics/software do weird things like my thread about Amimastergear emulator http://eab.abime.net/showthread.php?t=56838 that don't work right for me and that doesn't make any sense, and for others work like a charm, the only way to find out is try all possible combinations, it can drive you crazy! i know it all these years from computer and other hardware experience ,fortunately i 'm still sane somewhat

[roy bates]

thats why i was asking for a readout of the voltage from the brick end,car batterys are around 13.8-14.5 volts when fully charged

[Amiga1992]

I did that readout already, and it was 12.48V

[roy bates]

Originally Posted by Akira

I did that readout already, and it was 12.48V

ahh yes,you did indeed.

it doesent seem a high enough voltage to drive the picu(cant check myself ive given mine away to a freind along with a itx supply i dont need anymore)i think it should be around 13-13.8 to drive it from the switch.


just out of curiosity whats th voltage on the 5vsb line?

[Amiga1992]

It reads out 5V

If 12.48V wasn't enough, the picoPSU wouldn't work at all, but it does if jumpstarted and the Amiga shows NO sign of low voltage problems.

[roy bates]

If 12.48V wasn't enough, the picoPSU wouldn't work at all, but it does if jumpstarted and the Amiga shows NO sign of low voltage problems.[/quote]



yes,but thats because theres no load on the 12volt supply that drives the picu before you plug it in,if you see what i mean.

[Amiga1992]

No, I don't really understand.
I just want to use my computers

[roy bates]

im sorry,this must be very frustrating for you,and agian i apologise if you dont understand what i mean.


to be honest i would get a 12 volt 7 plus amp supply and try that.mainly becuase you have spent enough trying to get it to work under normal conditions.

good luck,akira.

[thgill]

Originally Posted by Akira

As I said I did try without the switch, but it still makes no sense. I tried another rocker switch, same result. Today I will try with a temporary switch.

You should be able to get a new replacement 60w brick for like $15 or so on ebay.

More than likely the brick can't supply enough juice to the pico psu under load to power it up (i.e. plugged into Amiga and then you switch the picopsu on) versus having the pico already turned on and running then plugged into the Amiga.


Think of it as lying down on a bench and pressing weights off your chest. With a heavy load you might not be able to get it up off your chest at all. However with a slight bit of help from a spotter, you can then press it completely up. Perhaps not the best analogy, however I don't think the brick can deliver the juice under pressure to power the amiga up correctly.

[Photon]

Would it be helpful to know that my PicoPSU 120W has worked fine with my A600 and A1200 in sig? Just needed a resistor between PS_ON and GND.

So could be the 12V brick. Try another 12V supply. Could be just a fuse or similar in your brick. The brick should light its own LED if it's okay, whether plugged in or not.

So there's no incompatibility using the Pico with Amigas that I know of. Check for shorts between voltages with the Amiga powered off, to make sure the Pico won't refuse to start because of a short.

[Amiga1992]

Originally Posted by Photon

Would it be helpful to know that my PicoPSU 120W has worked fine with my A600 and A1200 in sig? Just needed a resistor between PS_ON and GND..

Can you explain more about this? It might be the fix I need to apply for my setup to work.
What resistor?

[thgill]

There is no need for a resistor between ground and PS_ON.

[orange]

iirc, some people suggested connecting green wire (PS_ON?) to grey instead of GND with ATX supplies. dunno if there is such wire on that pico thingy. grey wire is supposed to signal that voltages are OK. perhaps it cannot provide enough amperes at -12V? it is unused in modern PCs.

[Photon]

Sound works fine on mine, and that's all it's used for. The Picos are way overkill for an Amiga, actually.

thgill: probably not, but usually a pulldown resistor is used to pull down active low signals, even if most input by far are designed to accept grounded inputs fine.

Akira: I figured you'd jump on this, but I don't think that's the problem. I use 1k Ohm I think, but I think anything from 10k down to 0 ohm will work.

My PicoPSU has a red and a green led on either side, and both light up when it's working. I think the red means the PicoPSU has a live input and green is the PS_ON input. But I'm not sure.

If there's no Amiga-short that would make the PicoPSU not turn on, I would try another PSU instead of the PicoPSU black laptopcharger-looking one.

And as always it's sound advice to connect just the "mobo" to test the PSU and then add expansions and connect monitor etc.