Question CMB operation on a portable ps2

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Hi, everyone!

I bought one of these chinese red CMB, just as recomended in another forum thread, but i just couldn't start it using a original ps2 power brick (8,4v). The seller says that charge voltage should be betwen 9 and 12V, so i decided to use my internet router 12v power brick. The CMB started. But...

I noticed that it outputs (Vout) 12v, same as the input (Vin) voltage and get a little confused.

How could it be an one port charge and play board if It deliveries 12v instead of the 8,4V required for ps2 operation? I checked the previous mentioned post again and notice that, in the depicted schemactics, Vout power goes straight to the portable power intrance. Is that correct? Do you guys use a DC voltage drop board to set Vout voltage the proper operation voltage, or are you just sending 12v straight into ps2? Should i use a 9v power brick? Does these PCB provide a balanced battery consumption just like in some BMS?

Hope you can help me.

Thanks!
 

Stitches

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The red board cheats. When it is supplied DC voltage, it shuts the batteries off and passes that supplied voltage on through a few diodes to the output. It will charge the batteries at a fixed rate of 1A while it does this. Most people use the PS2 version of the PMS now, as it solves this and several other problems.
 
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Thanks for your atention, Stitches!

I found one of these here in bit built store. I got a few questions about the product. Is there any place where i can find its instructions manual?
 
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Thanks again, Stitches!

I don't want to bother you, but could you answer me two questions about this PMS operation?

1 - These Built-in regulators 1.25v, 1.8v, 2.5v feature... It looks to me that there is no need to buy custom regulators in order to perform the advanced trim on my ps2 motherboard. Am i right?

2 - Could i use a 2S2P 18650 battery configuration?
 

StonedEdge

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1 - These Built-in regulators 1.25v, 1.8v, 2.5v feature... It looks to me that there is no need to buy custom regulators in order to perform the advanced trim on my ps2 motherboard. Am i right?
Yeah, no need for custom regulators. They are built into the PS2PMS so you can grab all the voltages you need from there.

2 - Could i use a 2S2P 18650 battery configuration?
No, the PS2PMS only supports a 1SxP configuration, X can be however many number of cells you want to wire up in parallel. It has a 5V boost regulator onboard for USB.
 
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Thanks again! I'will wait untill It get available on store again to put my hands on one of these boards.
 
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Thanks again! I'will wait untill It get available on store again to put my hands on one of these boards.
You can also just use a step down converter with that red board which is a little cheaper but adds more bulk. I did this with my build so I don't have to worry about accidently plugging in a 12v power supply while the switch is flipped on.
 
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You can also just use a step down converter with that red board which is a little cheaper but adds more bulk. I did this with my build so I don't have to worry about accidently plugging in a 12v power supply while the switch is flipped on.
I have these two, Bigbucther (pictures attached). The Blackboard one is the same as one of these red PCB's. The other is a DC-DC variable step down voltage. I was wondering if it will let enough current pass trough in order to feed the PS2 board.

Do you have, or could you draw by hand a simple schemactic depcting how you are using It on your project? Could you post It here?

Thanks for your answer!
 

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Stitches

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You can also just use a step down converter with that red board which is a little cheaper but adds more bulk. I did this with my build so I don't have to worry about accidently plugging in a 12v power supply while the switch is flipped on.
I have these two, Bigbucther (pictures attached). The Blackboard one is the same as one of these red PCB's. The other is a DC-DC variable step down voltage. I was wondering if it will let enough current pass trough in order to feed the PS2 board.

Do you have, or could you draw by hand a simple schemactic depcting how you are using It on your project? Could you post It here?

Thanks for your answer!

Imma countermand this advice and say do not do this. Using those cheapshit stepdowns is a bad idea, they have a history of catching fire at high load. It'd also neck the fuck out of your battery life. A better option would be to buy a 9V 3A power supply, and replace the default male barrel jack connector on it with a different connector. Perhaps a 2 pole high current JST connector like drone batteries use. Then you can put a matching female connector in your portable and it would prevent accidentally connecting a 12V DC supply to the system; and also not bring in the hugely uneccessary point of failure of a chinesium regulator.
 
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I have these two, Bigbucther (pictures attached). The Blackboard one is the same as one of these red PCB's. The other is a DC-DC variable step down voltage. I was wondering if it will let enough current pass trough in order to feed the PS2 board.

Do you have, or could you draw by hand a simple schemactic depcting how you are using It on your project? Could you post It here?

Thanks for your answer!
Yes that's exactly what I have, not sure how reliable the circuit is as Stitches has just explained that those step down converters are a bit iffy. I did not realise this and may change my circuitry at another time.

Here is a diagram i would suggest you follow instead.



1608319190632.png


If you end up using the step down converter (maybe there are safer ones available?), you would need to wire it up and use a flat head on that blue box to dial the stepped down voltage to be around 8.5v (You check this with a multimeter on the output of course). The converter is rated at a maximum input of 15v so I would use a 9-12v power supply to charge it. Preferably 9v for safety.

Here you can hopefully see how it's wired. The V out is connected through the converter then to the power switch, ground goes straight to the console obviously.

IMG_4933.jpg


Either that or you don't use a step down converter and you just be very careful not to flip the power switch when it is charging.

Final note, I think those cmbs have a protection feature if the batteries are disconnected at all so the cmb will not output anything more than 1V after you reconnect them. I have found plugging in dc and disconnecting will fix this and allow the full battery voltage to pass through again.

Hope this helps!
 
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Imma countermand this advice and say do not do this. Using those cheapshit stepdowns is a bad idea, they have a history of catching fire at high load. It'd also neck the fuck out of your battery life. A better option would be to buy a 9V 3A power supply, and replace the default male barrel jack connector on it with a different connector. Perhaps a 2 pole high current JST connector like drone batteries use. Then you can put a matching female connector in your portable and it would prevent accidentally connecting a 12V DC supply to the system; and also not bring in the hugely uneccessary point of failure of a chinesium regulator.
Thanks again, Stitches!

I'll take your advice untill PS2PMS is available.
 
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Yes that's exactly what I have, not sure how reliable the circuit is as Stitches has just explained that those step down converters are a bit iffy. I did not realise this and may change my circuitry at another time.

Here is a diagram i would suggest you follow instead.



View attachment 15364

If you end up using the step down converter (maybe there are safer ones available?), you would need to wire it up and use a flat head on that blue box to dial the stepped down voltage to be around 8.5v (You check this with a multimeter on the output of course). The converter is rated at a maximum input of 15v so I would use a 9-12v power supply to charge it. Preferably 9v for safety.

Here you can hopefully see how it's wired. The V out is connected through the converter then to the power switch, ground goes straight to the console obviously.

View attachment 15365

Either that or you don't use a step down converter and you just be very careful not to flip the power switch when it is charging.

Final note, I think those cmbs have a protection feature if the batteries are disconnected at all so the cmb will not output anything more than 1V after you reconnect them. I have found plugging in dc and disconnecting will fix this and allow the full battery voltage to pass through again.

Hope this helps!
Nice job you did with this portable, man! Congratulations!

You helped a lot, Bigbutcher! You gave me an Idea from another project. Thanks!

By the way, Bigbutcher... Have you ever been able to start this PCB with only 9v? Manufacturer says it is possible but i couldn't manage to turn it on with a voltage below 12v.
 
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Nice job you did with this portable, man! Congratulations!

You helped a lot, Bigbutcher! You gave me an Idea from another project. Thanks!

By the way, Bigbutcher... Have you ever been able to start this PCB with only 9v? Manufacturer says it is possible but i couldn't manage to turn it on with a voltage below 12v.
Hi, glad i could be of help! From my testing that step down converter does infact drain a lot of battery so may end up removing it.

For me, seems to charge very slowly at 9V, with a high pitch noise.

If i bump that up to 12V the high pitch noise is far less annoying, likely the inductor's doing.

I even managed to accidently plug 19V into it and it somehow survived before i realised it was only rated at 9v-15v. I have a spare at hand anyway haha.

I may go with Stitches advice with the JST connectors, I think it is possible to power the ps2 off 9V without frying it but I am not 100% sure. I have seen reports of people using aftermarket power supplies that are rated at 9V to power a non-portabalised ps2 and it working okay. Regardless I am not fussed about charging and playing at the same time so will be extra careful with the power switch. It would take a lot of bulk out of my build if i could remove the step down converter and be reassured it can handle that kind of voltage.

What is your cmb doing at 9V? Mine shows a red light which indicates it is charging with the high pitch noise. I am also using an adjustable power supply so I can see the amps lowering as the batteries reach their full capacity. Should be around 1amp.
 
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What is your cmb doing at 9V? Mine shows a red light which indicates it is charging with the high pitch noise. I am also using an adjustable power supply so I can see the amps lowering as the batteries reach their full capacity. Should be around 1amp.
My CMB was not even starting with 9v. But I checked the charger and found out that it was not working properly. So i replaced it with another one and now it is working well with 9v.

I had an idea for the voltage drop from 9v to 8,4v. I just couldn't test it, so i don't know if It will work, but you could perform tests and find out.

A diode should provide a 0,7v drop when used in series with the positive wire.

So, in theory, if you could find a diode capable to deal with ps2 working demands, you could solder It at the CMB positive line Vout straight to the PS2, and, in theory, It will provide enough voltage drop from 9v to 8,3v. You'll probably lose efficiency generating heat, but, maybe, it could be better than these chinese voltage drop boards. I don't know.

But please, If you intend to try this, perform some tests before.
 
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