Is my raspberry unrepairable?

You have most lightly blown something on the PI

The 4.3V battery should NOT have been connected between the 3.3V pin and the 5V pin, these are both seperate power + rails for parts of the PI board and you just put effectivly 8V into the 5V pin or caused excessive current to flow through pins not designed to have a difference of the battery or booster voltage.

What you should have done is connect the batter or booster output to 0V for the black wire and 5V for the red one (Using the booster to give you the 5V

you best option is actually to feed the 5V into the PI via the USB connection though, so battery to booster, booster to PI USB power connector

the schamatics have not been published but based on your description of how you connected a battery capapable of providing many amps between the 3V3 and 5V pins I would expect something to have failed

Sorry for the bad news, may the PI RIP.

Peter

So I cannot replace anything (nothing has physical damage except the pins, so I thought I may be able to replace them or even replace the led xd)? And one more question how can I put the black cable to 0v (because both cable where fused with the + and - of the boost output) ?

Thank for the fast responding! :O

Mauricio;

What John and Shabaz are saying is that you have to put your boost converter (or anything that supplies power: an actual power supply, buck/boost converter, transformer, etc.) under load (connect them into something that actually uses the power).  This can be a resistor (this is great as you know what the resistance is) or any kind of "black box" that uses a known combination of any two: voltage, current, or resistance.  It depends upon what the unknown is.  If you don't know current, you want to use a known voltage and resistance, for unknown voltage you use known current and resistance, for unknown resistance you use known current and voltage.  These are just the algebraic permutations of Ohm's Law: voltage=current x resistance (E=IR or V=IR, depending upon how you were taught).

I've got several nominal 12V/2A switching power supplies that are 15-16V without a load.  They drop to 11.8-12.5V under a minimum 220ohm load.  You won't get reliable measurement of what your power source is doing without putting it in the same conditions as expected when it's operating.  I once had a nominal 20VDC power converter that I didn't test - Just took the manufacturers specs.  It was at 28VDC with no load.  When I plugged the hot power supply into my circuit there was enough juice to let the magic smoke out of my 25V filter cap before the voltage dropped to the rated level.

You're welcome!

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Sorry, I don't know what went wrong with my email there.

What you need is a resistor ideally around 5 ohms rated at 5 watts or more, this will test your booster at the full output (I'm assuming your booster can provide around 1 amp). You connect it between the positive and zero volts connections at the output of the booster. Then get your multimeter and measure the voltage by placing the multimeter leads on either side of the resistor.

You might have made a mistake when you first set up your meter, as setting it to the 20V DC range should show be fine. Make sure you have turned it to the DC measurement range as you will get strange readings if set to the AC.

You could use a higher value resistor, but as you increase the value of the resistor the amount of current drawn from the power supply will go down. This can be important, as the booster might work fine at low currents and show around 5V, but as more current is needed by whatever it is connected to the voltage will drop considerably if the booster is faulty. Which is why you should try to test the booster near to the maximum current it might need to provide.

Colin

To substantiate Collins point about testing under load... A friend dropped by yesterday evening and asked me why his system didn't work. He has a DCDC converter (actually two) set for 13.6V, but they dropped to 10V under the intended load. (one always did so immediately, the other would sometimes hold out at 13.6V for a short while before dropping).

@Colin: resistors can be used outside their stated wattage without problems. In an experiment last week I needed a load for a 20V system. So grabbed the "cheap resistors" bag and the first one I pulled out was 100 ohms. 20V/100Ohms  = 200mA. That'll be fine for testing at first. But 200mA * 20V = 4W. So I grabbed 4 of the resistors, twisted them into 2S/2P configuration for quadruple the wattage = 4*0.25=1W. I'll stay below 1W by PWMing the thing at most 25%... Well you know how things go. When PWMing at 25% works you work your way up to 90 or 100%. Then you get the smell of burnt-electronics. Darn! Blew something up anway? Nope, just the resistors getting a tan.

I friend of mine did a similar mistake with its Pi. We unsoldered the switching regulator chip and the reset chip. Then, using a 1.8V LDO and a lab power supply set for 3.3V, we powered the 1.8V and the 3.3V rails of the board. We were amazed to see the processor and memory were still in working condition. You might try this approach as a last hope. Good luck

Hi!

Just wondering, is there a particular website that was followed that caused the issue? Perhaps that site is not doing a good job explaining exactly where to connect the signals. There are plenty of websites with poor (and incorrect) information unfortunately. Or could just be user error I guess.

But, as you say, there is a chance to get it functioning with this method. A bit difficult for a beginner though, who may never have used an LDO or lab supply.

In my friend's case, it was a plain mistake. He had the correct header pinout designations printed out, however he didn't focused and he connected the wrong pins for the power supply.

In my friend's case, it was a plain mistake. He had the correct header pinout designations printed out, however he didn't focused and he connected the wrong pins for the power supply.

Yes, if the battery capacity has at least a few hundreds of mAh. You need to use LDOs for all the power supply rails needed by the Broadcom CPU.

Unfortunately, as far as I know there's no available schematic for RPi 2. The schematics for the older boards are available but in order to be able to see if yours is still in working condition, you will need a working board to get some correct voltage measurements as reference. I can take mine tomorrow and measure the voltage in a few key places.

If you are plugging in a standard 5V 1A ish adapter to the USB power port and it is not powering up then its a pretty good bet it wont and something is fried based on the previous descriptions

At the end of the day it does not matter where the power comes from, if your feeding the right volts to the USB port and its not working then it is a conformation it is dead.

This assumes the power supply is good and the SD card is still functional (It too caould have been blown during the mix up of the power connections)

Peter

Yes pleas!!!! But first, is the "AMS1117-1.8V 3pins voltage regulator SMD chip LDO transistor 1.8v" a good one for the experiment?  Thanks!!