Lamprey Posted November 24, 2021 Share Posted November 24, 2021 Hi, I'm looking for some information about how to hook a power cable internal to the 99/4A that I can use to power a NanoPEB without the need for an external power supply just for the NanoPEB. Are there any guides for doing this or any info on the best place to "tap" into the power for the 5volts? There is a reference to doing this here by Stuart: Thanks! Quote Link to comment Share on other sites More sharing options...
+arcadeshopper Posted November 24, 2021 Share Posted November 24, 2021 Hi, I'm looking for some information about how to hook a power cable internal to the 99/4A that I can use to power a NanoPEB without the need for an external power supply just for the NanoPEB. Are there any guides for doing this or any info on the best place to "tap" into the power for the 5volts? There is a reference to doing this here by Stuart: Thanks!Basically it's not a good idea. The power supply and the ti are both old and probably not a good idea to add more load to them. In my opinion, it's safer to use an external power supply that's regulated because it requires a regulated power supplySent from my Pixel 6 Pro using Tapatalk 3 Quote Link to comment Share on other sites More sharing options...
+OLD CS1 Posted November 25, 2021 Share Posted November 25, 2021 FWIW, the nanoPEB will run off a good USB charger with the proper barrel connector. I run mine like that often. I stress "GOOD" USB charger. Far too many of them do not output or hold at 5V, or reference the negative (0V) rail to utility neutral (introduces a buzzing and potential potential difference between the console and nanoPEB power supplies.) For portability, I have run my nanoPEB and CF7+ off a USB battery pack. Quote Link to comment Share on other sites More sharing options...
wierd_w Posted November 25, 2021 Share Posted November 25, 2021 (edited) On thing I have considered making, is a "Bulk passthrough except 5v Rail" sidecar, that accepts a single input from external source, and provides a robust +5V rail. Basically clips the 5V rail intended for the speech synth, attaches the GND line of the barrel connector to the GND of the card edge, then substitutes the +5V from the barrel connector on the +5V line of the outbound side of the card edge. This would isolate the TI's motherboard, except for the ground plane (so that there is no ground difference between sidecars and the console), and allow power hungry devices to operate without an additional wall wart. Perhaps throw in a buck regulator? Accept commodity 12V or 19V input (cheap laptop power adapter), and output regulated 5V? (perhaps multiple ones in parallel, so that you can have more amperage draw before tanking the regulated 5v? For safety reasons, you wouldnt want to go higher than 2A on a thin circuit trace anyway, and 2A is pushing it. Risk of vaporizing the trace would be real high if you put that much load on it.) That would let a single wall wart supply handle the whole sidecar chain. Edited November 25, 2021 by wierd_w 1 Quote Link to comment Share on other sites More sharing options...
Lamprey Posted November 25, 2021 Author Share Posted November 25, 2021 Thanks for the replies. It gives me something to think about. I'd have to test it, but I thought the NanoPEB draws less than 100mA. Assuming that is true, that doesn't seem like much of a draw to tap off of the internal power supply of the TI. But, perhaps the low overhead coupled with age would push the power supply over it's limits..? @wierd_w I'm only running the speech synth and the NanoPEB on the side car chain. So, it shouldn't be drawing too many amps. I'm still thinking of adding a 5volt jumper to my speech synth and see if it can pass power to the NanoPB (and have it work). Seems like it is hit or miss with people doing that. Something to think about while eating some Turkey tomorrow! 1 Quote Link to comment Share on other sites More sharing options...
wierd_w Posted November 25, 2021 Share Posted November 25, 2021 The +5v rail supplied by the TI can, at most, supply 500mA, and that really is stressing the TI PSU module. The NanoPEB needs a fair bit more than that to operate properly, IMO. A TIPI needs even more. Quote Link to comment Share on other sites More sharing options...
GDMike Posted November 25, 2021 Share Posted November 25, 2021 Get a TIpi and your TI will grow up quick. Quote Link to comment Share on other sites More sharing options...
Lamprey Posted November 25, 2021 Author Share Posted November 25, 2021 6 hours ago, GDMike said: Get a TIpi and your TI will grow up quick. I originally bought a TIPI because I thought the NanoPEB and C7+ were no longer available. But, I want something that I don't have to worry about shutting down ever time before I power it off. So, the nanopeb is a better option for me. 1 Quote Link to comment Share on other sites More sharing options...
GDMike Posted November 25, 2021 Share Posted November 25, 2021 (edited) 2 minutes ago, Lamprey said: I originally bought a TIPI because I thought the NanoPEB and C7+ were no longer available. But, I want something that I don't have to worry about shutting down ever time before I power it off. So, the nanopeb is a better option for me. I haven't shut down my TIpi in over 4 months. It's a pretty sturdy little pi. But I understand what you're saying. But I don't believe those nanopebs are being made any longer. Edited November 25, 2021 by GDMike Quote Link to comment Share on other sites More sharing options...
Stuart Posted November 25, 2021 Share Posted November 25, 2021 9 hours ago, wierd_w said: The +5v rail supplied by the TI can, at most, supply 500mA, and that really is stressing the TI PSU module. The NanoPEB needs a fair bit more than that to operate properly, IMO. A TIPI needs even more. I suspect you meant 50mA, not 500. That's the amount the spec says you can draw from the sideport connector. My NanoPEB draws around 80mA max. I'm sure a GRAM Kracker, powered through the cartridge port, must draw something similar, and you can add to that a cartridge with several ICs and a speech synth, so I don't think there's a problem with the internal PSU supplying the power. You can make up a power lead and solder it direct the output connector on the PSU, and try it with your NanoPEB without having to make any other mods to the console at all. If you find it unreliable then you can unsolder the cable and your console is back as it was. 2 Quote Link to comment Share on other sites More sharing options...
wierd_w Posted November 26, 2021 Share Posted November 26, 2021 11 hours ago, Lamprey said: I originally bought a TIPI because I thought the NanoPEB and C7+ were no longer available. But, I want something that I don't have to worry about shutting down ever time before I power it off. So, the nanopeb is a better option for me. I would have to dig deeper into which pins on the GPIO header the TIPI lives on, but there is a robust selection of GPIO based UPS hats for the raspberry pi that could be added to your TIPI (manual configuration! they expect you to be comfortable mucking with the PI's root console!) that would allow it to sit out a momentary power blip, and then initiate safe shutdown (and then actually power off, in some models) once a certain time-on-battery threshold has been reached. Again though, I would have to look at which GPIOs are being used by the TIPI's interface cable, and seek a UPS hat that does not use the same ones. 1 Quote Link to comment Share on other sites More sharing options...
Lamprey Posted November 26, 2021 Author Share Posted November 26, 2021 15 hours ago, wierd_w said: I would have to dig deeper into which pins on the GPIO header the TIPI lives on, but there is a robust selection of GPIO based UPS hats for the raspberry pi that could be added to your TIPI (manual configuration! they expect you to be comfortable mucking with the PI's root console!) that would allow it to sit out a momentary power blip, and then initiate safe shutdown (and then actually power off, in some models) once a certain time-on-battery threshold has been reached. Again though, I would have to look at which GPIOs are being used by the TIPI's interface cable, and seek a UPS hat that does not use the same ones. Yeah, that could be a nice solution to shut down the TIPI. I'm just going with the NanoPEB, so no worries here. Quote Link to comment Share on other sites More sharing options...
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