Hello x, you might include FDP045N10A / FDI045N10A as alternatives as they have slightly more suitable characteristics.
Although , stock is limited to just 18 qty on mouser. 1000 more might be available by June 15th as per mouser site.
Also STP130N8F7, IPA037N08N3...
regards
Prasi
baswamin - 2 boards - Paid
meanie - 2 boards - Invoice sent
jwjarch - 2 boards - Paid
gary s - 2 boards - Paid
nautibuoy - 2 boards - Need PayPal address
antoniopf1972 - 2 boards - Paid
ravid - 2 boards - Paid, Invoice sent for Simple PSU ship same time
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yoaudio - 2 boards
vanofmonks - 1 board
meanie - 2 boards - Invoice sent
jwjarch - 2 boards - Paid
gary s - 2 boards - Paid
nautibuoy - 2 boards - Need PayPal address
antoniopf1972 - 2 boards - Paid
ravid - 2 boards - Paid, Invoice sent for Simple PSU ship same time
Gricko - 2 boards - Invoice sent
poseidonsvoice - 2 boards - Paid
Bkdog - 2 boards - Invoice sent
yoaudio - 2 boards
vanofmonks - 1 board
Thanks for the tip, Prasi. Those do look nice with 5.6mOhm Rdson. I already got my 16 in hand and soldered up. Maybe next set of boards. Although the ones Jhofland spec’d pretty good ones. I forget what the Rdson is big also pretty low.
This device seems to be in high demand from all suppliers, Arrow had hundreds of them when I purchased at $0.69 USD each. Now they have practically none left at a higher price now, although they are showing the original ST Micro part with a few hundred in stock at $1.25 USD each.
When I contacted Arrow at purchase they said the prices change every day and it is the manufacturer who sets the price and not Arrow!
So it pays to look around from the usual suppliers when doing a purchase for out of the ordinary type items - especially semi conductors.
When I contacted Arrow at purchase they said the prices change every day and it is the manufacturer who sets the price and not Arrow!
So it pays to look around from the usual suppliers when doing a purchase for out of the ordinary type items - especially semi conductors.
SLB Verification Build Testing
I built up the verification build PCB and managed to do some testing today using a pair of big 100w 8ohm resistors (8 ohms single and 16 ohms in series). The trafo was an Antek AN 3232 (300VA 32v) and first thing I noticed is that the active rectifier MOSFETs are barely warm (40C) under 4.3A load and not even noticeable at 2.15A load. So the LT4320 and the selected MOSFETs are working out very well. It is so refreshing not to have heat or huge heatsinks for the rectifier of a big Class A PSU.
Under 4.3A load and 35V out with a 3.5V dropout, I measure about 7mVpp ripple. Under 2.15A load and 37V out, I measure under 1mV ripple - it is hard to see because the radiated noise pickup in the lab with the PSU turned of is about 4 to 5mVpp.
Here is the setup:
Here is a closeup of the verification build:
Here is the O-scope shot of the noise pickup in the lab with PSU turned off:
For 2.15A load using a 16ohm resistor, here is the ripple upstream of the cap Mx at the output of the CRC we get about 287mVpp for 37v at the load:
Here is the output of the SLB at the load resistor or downstream of the cap Mx, we barely get any visible ripple - probably under 1mV. Compare this to 287mVpp from just the CRC. Typical 25w Class A amp CRC's are using maybe 33,000mF and about 0.11R so probably half this for circa 120mV to 140mVpp ripple. With the SLB in place, there should be absolute silence in the black background - no more 60Hz hum:
For the 4.3A load case, the temperature of the 0.1R KOA BPR resistors was measured to be about 73C. I was able to touch it for a few seconds but without applying heavy squeeze pressure. It's not a burn hazard as you can easily retract your fingers in time. At the typical 2.15A to 2.5A load that folks will be using this as a PSU for a Pass 25w Class A amp, the temp is much lower and it should not be a problem at all:
The SLB is now verified to work, but I did notice that the current 200ohm pot does not give much of an adjustment range. So I will work with Hugh and Jhofland on that - probably a few minor changes to some resistors should do the trick. For the production unit, I have asked Jfoland to add more output spade terminals so that one SLB can power a stereo amp and also have returns for the speakers. Having a built in GLB with an NTC and 22nF cap on board is nice to reduce the amount of ancilliary stuff that needs to be done.
I built up the verification build PCB and managed to do some testing today using a pair of big 100w 8ohm resistors (8 ohms single and 16 ohms in series). The trafo was an Antek AN 3232 (300VA 32v) and first thing I noticed is that the active rectifier MOSFETs are barely warm (40C) under 4.3A load and not even noticeable at 2.15A load. So the LT4320 and the selected MOSFETs are working out very well. It is so refreshing not to have heat or huge heatsinks for the rectifier of a big Class A PSU.
Under 4.3A load and 35V out with a 3.5V dropout, I measure about 7mVpp ripple. Under 2.15A load and 37V out, I measure under 1mV ripple - it is hard to see because the radiated noise pickup in the lab with the PSU turned of is about 4 to 5mVpp.
Here is the setup:
Here is a closeup of the verification build:
Here is the O-scope shot of the noise pickup in the lab with PSU turned off:
For 2.15A load using a 16ohm resistor, here is the ripple upstream of the cap Mx at the output of the CRC we get about 287mVpp for 37v at the load:
Here is the output of the SLB at the load resistor or downstream of the cap Mx, we barely get any visible ripple - probably under 1mV. Compare this to 287mVpp from just the CRC. Typical 25w Class A amp CRC's are using maybe 33,000mF and about 0.11R so probably half this for circa 120mV to 140mVpp ripple. With the SLB in place, there should be absolute silence in the black background - no more 60Hz hum:
For the 4.3A load case, the temperature of the 0.1R KOA BPR resistors was measured to be about 73C. I was able to touch it for a few seconds but without applying heavy squeeze pressure. It's not a burn hazard as you can easily retract your fingers in time. At the typical 2.15A to 2.5A load that folks will be using this as a PSU for a Pass 25w Class A amp, the temp is much lower and it should not be a problem at all:
The SLB is now verified to work, but I did notice that the current 200ohm pot does not give much of an adjustment range. So I will work with Hugh and Jhofland on that - probably a few minor changes to some resistors should do the trick. For the production unit, I have asked Jfoland to add more output spade terminals so that one SLB can power a stereo amp and also have returns for the speakers. Having a built in GLB with an NTC and 22nF cap on board is nice to reduce the amount of ancilliary stuff that needs to be done.
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The heat is confined to the pass transistor mounted on the convenient AMP connector with flying leads. You can mount it anywhere convenient, like the chassis floor or the main side heatsink. On the board itself, the KOA resistors can get to 73C if you are runninng a huge load like 4.3A. But for 1.25A or 2.5A loads, it's not even an issue.
Size of the final board is a bit larger to accommodate more spade terminals on the output. Here is the outline and parts. It is 150mm x 100mm in size. Height will be the height of the 15,000uF caps (about 42mm to 45mm tall).
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GB Status Update:
Sorry, I don't really have spares of the LT4320 to include in the order. They are available on Mouser here:
LT4320IN8#PBF Analog Devices | Mouser
Sorry, I don't really have spares of the LT4320 to include in the order. They are available on Mouser here:
LT4320IN8#PBF Analog Devices | Mouser
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Very good work. It looks all very neat and beautiful. And it also works as expected. Congratulations. I already have to try to see how it goes. I have all the components ordered in Mouser. And I have two symmetrical 30v transformers in alternating. I hope not of too much tension at the exit, once rectified