Thread split from here - PO89ZB , an inline DC filter for SMPS wall warts . Preamps, HPA, Korg NuTube, etc Could you please suggest ways we can get low power dual / split supply say +/-5v or +/-12v supply from the external wall switcher supply, which we can use for preamps.
Not sure who you are addressing at but why not build 2 x PO89ZB and reverse D1, C1 and C2 on the negative board? Feed them with a symmetric SMPS if you can find one. Any attempt to split voltage on a standard single voltage SMPS is futile I would say.
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means do we need to use 2 wall switcher for getting +/- split voltage?
can we have a single one wall switcher externally and generate dual +/- voltages on the boards for preamp requiring +/- voltages.
can we have a single one wall switcher externally and generate dual +/- voltages on the boards for preamp requiring +/- voltages.
Creating 2 voltages + and - from a single voltage SMPS is futile so you need 2 yes. If you want quality you better build a linear PSU with a dual secondary transformer. Easy, best and no PO89ZB necessary. PO89ZB is a cure to make existing switchers less noisy. No switcher = way less noise straight away. If you have the choice and need to start fresh anyway choosing a good old quality transformer is the way to go. Using 2 wall warts occupying 2 Schuko slots with the risk one of them being unplugged (or failing) and possibly destroying the device they feed is an unwanted risk I think.
From the same designer: VRDN: bipolar regulator PCB for line level ckts: ±11V to ±20V @ 1.5A with "De-Noiser"
Or build something ultra low noise with modern LDO regs without denoiser.
Despite popular design culture linear PSU's are way less noisy and the best SMPS still needs a ultra low noise linear reg to make it really quiet. Good quality transformers rarely die contrary to SMPS which are built to fail in consumer stuff it seems.
From the same designer: VRDN: bipolar regulator PCB for line level ckts: ±11V to ±20V @ 1.5A with "De-Noiser"
Or build something ultra low noise with modern LDO regs without denoiser.
Despite popular design culture linear PSU's are way less noisy and the best SMPS still needs a ultra low noise linear reg to make it really quiet. Good quality transformers rarely die contrary to SMPS which are built to fail in consumer stuff it seems.
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ESP has Project 43 which does the job and TLE24256 works as well. Both use a virtual ground. There are other schemes such as those used by Silicon Chip magazine.
Project 43 - Simple DC Adapter Power Supply
I've also tried a Traco Power TMR3 DC converter but needs caps and regs after the output. For ±15VDC output from a Traco you need 12V regs etc to give ±12VDC. Wasn't the quietest supply IIRC.
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Hi, I think we can estimate the performance of such a device with virtual GND.
So, a cheap SMPS followed by a virtual GND circuit creating +/- voltages (severely limited current available), then 2 x PO89ZB if the opamp can accept PO89ZB...which is not the way PO89ZB was meant to be used (I think) as it was meant to clean up an SMPS directly...
Or a cheap SMPS followed by a PO89ZB, then the virtual GND circuit creating +/- voltages for a whopping 40 mA of maximum current.
What will be the benefit compared to a small transformer, some diodes and good regulators?
So, a cheap SMPS followed by a virtual GND circuit creating +/- voltages (severely limited current available), then 2 x PO89ZB if the opamp can accept PO89ZB...which is not the way PO89ZB was meant to be used (I think) as it was meant to clean up an SMPS directly...
Or a cheap SMPS followed by a PO89ZB, then the virtual GND circuit creating +/- voltages for a whopping 40 mA of maximum current.
What will be the benefit compared to a small transformer, some diodes and good regulators?
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Saves playing with mains voltages and suitable for micro cased projects. Enough grunt for a couple of op amps. There was no mention of para 2 & 3 in sarathssca's question.
Of course you can use a AC power plug pack like Rod uses in his ESP 05 mini. That way you have caps and regs for a better supply.
P05-Mini
I'm sure you will find something wrong with that as well.
Note: error in post #55.... should read TLE2426.
Of course you can use a AC power plug pack like Rod uses in his ESP 05 mini. That way you have caps and regs for a better supply.
P05-Mini
I'm sure you will find something wrong with that as well.
Note: error in post #55.... should read TLE2426.
Nothing wrong with that (though better regs exist) as it is a textbook linear power supply. It will be way cleaner than the cheap SMPS and is better suited as symmetrical PSU. If quality is the goal as I see a difference in approach.
The trend to include SMPS is not because these are better. If one has choice choose for best quality not for noisy cheap solutions. Sometimes it is unavoidable as it is a design choice based on cost cutting (PO89ZB comes to the rescue) but in most cases the clever DIYer can come up with a better solution. It may involve working with mains voltages but how will one gain experience otherwise?
The trend to include SMPS is not because these are better. If one has choice choose for best quality not for noisy cheap solutions. Sometimes it is unavoidable as it is a design choice based on cost cutting (PO89ZB comes to the rescue) but in most cases the clever DIYer can come up with a better solution. It may involve working with mains voltages but how will one gain experience otherwise?
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ya one of the point was to avoid directly using mains voltage, also it was for using with the ACA amp which already using external laptop SMPS supply, so thinking to derive power for preamp from same supply.
It really is better to give all available information at once for better suited advice. Maybe you can start a separate thread and have the mods move all posts regarding your question (as it has nothing to do with PO89ZB)?
edit: I asked the mods already.
edit: I asked the mods already.
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Scrap my suggestions as they will not work with a shared SMPS supply as shown in the thread below.
Subwoofer amp and controller from the same power supply
They need their own supply except for the Traco TMR3.
Subwoofer amp and controller from the same power supply
They need their own supply except for the Traco TMR3.