No, I hadn't try the AD/TI search functions. There might be LT models to simulate too.
Yes, there are negative regulators to use with the LT3042 @ 15v.
There are also options to be used with higher voltages, although for up to 80v input only with 60v max output. Not the 68v I'd be interested in.
It's unlikely I will find eBay reg pcbs using any of these chips, but I will look into that. There's always the evaluation kits, but they will certainly be rather expensive.
Yes, there are negative regulators to use with the LT3042 @ 15v.
There are also options to be used with higher voltages, although for up to 80v input only with 60v max output. Not the 68v I'd be interested in.
It's unlikely I will find eBay reg pcbs using any of these chips, but I will look into that. There's always the evaluation kits, but they will certainly be rather expensive.
No, I hadn't tried the AD/TI search functions. There might be LT models to simulate too.
Yes, there are negative regulators to use with the LT3042 @ 15v.
There are also options to be used with higher voltages, although for up to 80v input only with 60v max output. Not the 68v I'd be interested in.
It's unlikely I will find eBay reg pcbs using any of these chips, but I will look into that. There's always the evaluation kits, but they will certainly be rather expensive.
Yes, there are negative regulators to use with the LT3042 @ 15v.
There are also options to be used with higher voltages, although for up to 80v input only with 60v max output. Not the 68v I'd be interested in.
It's unlikely I will find eBay reg pcbs using any of these chips, but I will look into that. There's always the evaluation kits, but they will certainly be rather expensive.
Now THIS looks very interesting!
LT3045 LT3094 positive and negative regulated linear power supply +-5/9/12/15V | eBay
Or this:
LT3045 LT3094 Positive and Negative Low Noise Regulated Linear Power Supply for | eBay
The one with the heatsink below seems to allow using an external input, where we can implement a CRC input filter, that seemed to influence PSRR quite a bit on my simulations.
LT3045 LT3094 positive and negative regulated linear power supply +-5/9/12/15V | eBay
Or this:
LT3045 LT3094 Positive and Negative Low Noise Regulated Linear Power Supply for | eBay
The one with the heatsink below seems to allow using an external input, where we can implement a CRC input filter, that seemed to influence PSRR quite a bit on my simulations.
It means that inputs can withstand negative up to 22V voltage (it won't burn, and won't work, of cause).
LT3081 would need help to improve its PSRR. Input CR(L)C filter comes to mind. Ideally I would think of using a DC-DC converter in front of it which allows for much lower CR(L)C components values to achieve >100dB extra PSRR at the switching frequency. Doing it for 50 or 60 Hz mains frequency requires large capacitance and either relatively big value resistor which increases the voltage drop and lowers efficiency or large size choke.
Considering the actual parts size, the caps, particularly the more critical output ones, seem to be around 10mm off, which I'm not sure it's not within specs.
Only getting one and checking that with a ruler would answer that.
I'm much concerned about the actual schematic they used, and, as you also raise, how they could get that price to be that low.
Either fakes or a large batch they could get from someone else that sold them for a lower price.
To check the first option only actual measurements can answer that.
In any case, the bet is low to try it to power an actual circuit. Which in my case would be a RIAA preamp.
Yes, that's what I seemed to notice in my LT3081 simulations, which I thought were wrong because they were worst than the ones I had achieved even with a discrete regulator, which I can show you for you to see.
So I thought my implementation is wrong, and why I asked for a working schematic.
Probably you didn't see them, but there are a few threads dealing with remarkable regulators, some even as good or better than the superregulators.
I googled and didn't find that article on fake 3045.
What do you think about those 3042 eBay boards that I showed? Are they fake too?
For some reason I can't find it either.. Some of the cheapest boards were fakes with wrong package markings regarding package type or wrong number of legs. So check the Ti's datasheet regarding numbering and count the legs on the chip to improve the likelihood of getting a real one. Perhaps someone on this forum have measured their cheap LT3042?
OK, folks. Coming back just to update.
The regulators I need are to be used on a phono preamp, so you will need a very low noise supply.
I could simulate plenty of them, some of the best were measured by John Walton on Linear Audio.
https://linearaudio.nl/sites/linearaudio.net/files/v4 jdw.pdf
I am working on opening another thread with the simulations I did, compared to the actual Walton results.
Now you can find the LT3045 in a small version that you can use to replace a fixed voltage 3-pin regulator. Price is reasonable.
https://pt.aliexpress.com/item/1005...c16709322398561672e52ba!12000025008751691!rec
These folks, who probably also designed this 3-pin adapter, sell a V+/V- power supply, at a very reasonable price.
The LT chips excel at noise and PSRR, but they are not as good as others on impedance.
I can upload the asc files from the simulations I did, if anyone is interested.
There's a new family of regulators that use 3X7 regulators existing supplies, and you add a small pcb called "denoisator" and it improves all measured figures by a large margin.
But the most reliable high end power supply still continues to be the Jung/Didden design called Super regulator. Now you can buy the two pcbs for V+/V- regulators, buy all the listed parts, easily available in Mouser, and have a state of the art PS.
The regulators I need are to be used on a phono preamp, so you will need a very low noise supply.
I could simulate plenty of them, some of the best were measured by John Walton on Linear Audio.
https://linearaudio.nl/sites/linearaudio.net/files/v4 jdw.pdf
I am working on opening another thread with the simulations I did, compared to the actual Walton results.
Now you can find the LT3045 in a small version that you can use to replace a fixed voltage 3-pin regulator. Price is reasonable.
https://pt.aliexpress.com/item/1005...c16709322398561672e52ba!12000025008751691!rec
These folks, who probably also designed this 3-pin adapter, sell a V+/V- power supply, at a very reasonable price.
The LT chips excel at noise and PSRR, but they are not as good as others on impedance.
I can upload the asc files from the simulations I did, if anyone is interested.
There's a new family of regulators that use 3X7 regulators existing supplies, and you add a small pcb called "denoisator" and it improves all measured figures by a large margin.
But the most reliable high end power supply still continues to be the Jung/Didden design called Super regulator. Now you can buy the two pcbs for V+/V- regulators, buy all the listed parts, easily available in Mouser, and have a state of the art PS.