Great thanks.
And sorry I forgot to ask.....is it ok to pre reg with lm317 before the SimpleMx to alleviate some heat from it ...so the voltage drop isn't so large on the SmX..?
I have some 317 boards...some toroids and rectifiers I would like to use up, but it will get me a higher voltage than comfortable to feed into the Smx to reg down to 5v for Rpi
And sorry I forgot to ask.....is it ok to pre reg with lm317 before the SimpleMx to alleviate some heat from it ...so the voltage drop isn't so large on the SmX..?
I have some 317 boards...some toroids and rectifiers I would like to use up, but it will get me a higher voltage than comfortable to feed into the Smx to reg down to 5v for Rpi
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C113
Need to ask a stupid question, I am not used to seeing capacitor values listed the way its shown on the BOM for C113, 2u2, what is this value?
Thanks,
Bill
Need to ask a stupid question, I am not used to seeing capacitor values listed the way its shown on the BOM for C113, 2u2, what is this value?
Thanks,
Bill
Yes, the R (k or M), or u (Greek mu) or n (nano) or p (pico) is placed at the decimal.
For example 2R2 is 2.2 ohms, 2k2 is 2200 ohms, 2M2 is 2,200,000 ohms
2.2uF is 2.2 micro Farads, 2u2 is same, but with caps, M is sometimes used for Micro rather than Mega, so 2.2M is 2.2 micro Farads. And 2n2 is 2.2 nano Farads or 0.000022 Farads, and 36p is 36 pico Farads, etc.
For example 2R2 is 2.2 ohms, 2k2 is 2200 ohms, 2M2 is 2,200,000 ohms
2.2uF is 2.2 micro Farads, 2u2 is same, but with caps, M is sometimes used for Micro rather than Mega, so 2.2M is 2.2 micro Farads. And 2n2 is 2.2 nano Farads or 0.000022 Farads, and 36p is 36 pico Farads, etc.
I got my two boards mostly assembled, waiting on some tpsa regs to arrive. So while I'm waiting for them to get here, I'm trying to figure out layout in my prototype chassis.
I'm using a 2x 9v/2x 15v toroidal transformer to feed into Salas' 'DC Flexy' boards that will feed into the cap-mx regulated supplies.
1 will feed the TDA1387 DAC Hat from Matt Garman.
1 will feed the Allo Kali re-clocker.
There is also a tpsa* regulated supply in there to feed the pi directly.
Hopefully the ebay tpsa regs get here soon, so I can wrap up and start listening!
The cap-mx supply boards are super easy to assemble, nicely laid out and a decent size. I used parts from my stash mostly, so some of the components choices may be a bit odd.
I'm using a 2x 9v/2x 15v toroidal transformer to feed into Salas' 'DC Flexy' boards that will feed into the cap-mx regulated supplies.
1 will feed the TDA1387 DAC Hat from Matt Garman.
1 will feed the Allo Kali re-clocker.
There is also a tpsa* regulated supply in there to feed the pi directly.
Hopefully the ebay tpsa regs get here soon, so I can wrap up and start listening!
The cap-mx supply boards are super easy to assemble, nicely laid out and a decent size. I used parts from my stash mostly, so some of the components choices may be a bit odd.
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That’s an impressive setup. What is it? An RPi music streamer?
If you want to get started try run of the mill 78xx to get things fired up and swap out with the TPSA regulators later.
If you want to get started try run of the mill 78xx to get things fired up and swap out with the TPSA regulators later.
Yes sir, streamer box that I'll ultimately put in the main system.
I might do just that, I'm sure I've got some in my stash. I need to figure some heatsinking option for the regulators on the flexy boards. I have a bunch of to-220 heatsinks of various sizes, but I would rather mount them to a single heatsink of some sort. I have some 18mmx18mm aluminum bar stock, I could make a piece for each side for the regs to bolt to, and the bars then bolt down to the chassis. That might work well. Ultimately, I would like to find a good solution that is as space efficient as possible. I want to build a chassis for all the bits, and ideally make it not enormous, haha.
To quote (sorta) John Goodman from Raising Arizona:
"So many regulated power supplies, so little room"
something like that......
Regs in use
X, thanks for this great project. I'm using 2 of these boards to power the BeagleBone and DSC2 in my new networked 1-bit discrete DSD DAC. Some pictures and details are at https://www.diyaudio.com/forums/digital-line-level/254935-signalyst-dsc1-141.html#post5830294.
Overall it is working great, I'm feeding it 12v from a nice SMPS (https://www.cui.com/product/resource/sdm36-u.pdf). For the DSC2 I am using a TPS7A4701 regulator board from eBay (TPS7A4701 Low Noise RF LDO Regulator Power Supply Module 1.5V-34V 3.3V 5V 12V 1A | eBay). For the BeagleBone Green I'm using a LM340AT-5.0 (http://www.ti.com/lit/ds/symlink/lm340.pdf). I had originally used a a MIC29300-5.0WT 3A LDO for this supply, but turns out it won't regulate without a load, which in turn causes the BeagleBone to go into overvoltage protection...
One hiccup I've run into using this for the BeagleBone is the slow voltage ramp time of the cap mx. The BeagleBone's PMIC goes into a fault if the voltage does not reach 5v within 50ms. To solve this problem, I think I am going to put a load switch IC in-between the PSU and the BeagleBone and wire the EN pin of the load switch using a resistor divider to only enable the output when the power is close to 5v. This is shown in section 9.3.1 of http://www.ti.com/lit/ds/symlink/tps22953.pdf for the IC I am considering. Has anyone used something similar in a scenario like this?
X, thanks for this great project. I'm using 2 of these boards to power the BeagleBone and DSC2 in my new networked 1-bit discrete DSD DAC. Some pictures and details are at https://www.diyaudio.com/forums/digital-line-level/254935-signalyst-dsc1-141.html#post5830294.
Overall it is working great, I'm feeding it 12v from a nice SMPS (https://www.cui.com/product/resource/sdm36-u.pdf). For the DSC2 I am using a TPS7A4701 regulator board from eBay (TPS7A4701 Low Noise RF LDO Regulator Power Supply Module 1.5V-34V 3.3V 5V 12V 1A | eBay). For the BeagleBone Green I'm using a LM340AT-5.0 (http://www.ti.com/lit/ds/symlink/lm340.pdf). I had originally used a a MIC29300-5.0WT 3A LDO for this supply, but turns out it won't regulate without a load, which in turn causes the BeagleBone to go into overvoltage protection...
One hiccup I've run into using this for the BeagleBone is the slow voltage ramp time of the cap mx. The BeagleBone's PMIC goes into a fault if the voltage does not reach 5v within 50ms. To solve this problem, I think I am going to put a load switch IC in-between the PSU and the BeagleBone and wire the EN pin of the load switch using a resistor divider to only enable the output when the power is close to 5v. This is shown in section 9.3.1 of http://www.ti.com/lit/ds/symlink/tps22953.pdf for the IC I am considering. Has anyone used something similar in a scenario like this?
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Nice setup Gtose! Thanks for the idea with the load switch IC. Never knew about such a part before. Might come in really handy. Let me know if it works for you. One of the nice things about the cap Mx was the slow turn on ramp which prevents thump in a lot of amps but in this case, the system doesn’t like slow starts.
It's also a great feature to prevent inrush and over current shutdown on some SMPSes. I guess you can't please all use cases! I'll let you know how the load switch works out.
Finally got round to building one of these. Included in my DAC project to feed the RPI. Works very well! Definitely an improvement from feeding the RPI directly from an SMPS.
Nice work, Maartn. What regulator are you using because doesn’t an RPI take more than 1A at 5v? These digital streamer projects using RPI look like a lot of fun. Glad that this little simple PSU is able to help provide clean power.
A new batch of boards just arrived - available in my shop here:
Simple Cap Mx Regulated Power Supply | Etsy
Simple Cap Mx Regulated Power Supply | Etsy