Yeah... But it's going to arrive pretty soon now
Soldered the second pcb without 9610s while waiting. Also running the TH version in my system now - plays very nicely. Low phase shift rules
I've been looking into SMT complementary devices in a single package. These look promising. http://www.mouser.com/ds/2/308/BC846BPDW1T1-D-111237.pdf
Rather interesting observation
I have compared the Shuntie's regulation efficiency with IRFP9240 and IRF610 transistors (in simulation).
Ingesting 50mv ripple at the input (70V rails), I have at the output:
- IRFP9240 - 400nV;
- IRF9610 - 1500nV.
The reason is the difference in their Rds(on):
- IRFP9240 = 0.38R (up to 0.5R);
- IRF9610 = up to 3R.
Well, both results are very good. But the first one is slightly better
I have compared the Shuntie's regulation efficiency with IRFP9240 and IRF610 transistors (in simulation).
Ingesting 50mv ripple at the input (70V rails), I have at the output:
- IRFP9240 - 400nV;
- IRF9610 - 1500nV.
The reason is the difference in their Rds(on):
- IRFP9240 = 0.38R (up to 0.5R);
- IRF9610 = up to 3R.
Well, both results are very good. But the first one is slightly better
Possibly yes, but the level of 400nV from 50mV is already rather cool
It will also require certain topology changes, as those Infineon devices are all N channel...
Hi Sam, I'm really not sure there will be some benefit. IRFs work very well in these conditions.
Thank you for the feedback.
What changes would you recommend if the OPS is to be changed to N-channel Mosfets only? Thanks.
These have been available for a long time now. I like/try to use/search for parts in 50miil soic,sot-23, sod-123 packages, if they are avail. for passive R, i try to use 0805/1206/1210 etc for these types of designs. Susumu are nice thin film R parts to use.
i read that the onsemi tl431 has the lowest noise of all the mfgs.
Enjoy your trip and show/conference !! What are you presenting? It is the national assoc of Broadcasters?
Any problem with declaring parts with the immigration officers? Just hand them the load of paper they send with the orders, it is unbelievable how much paper they send with the orders.
A very small chisel tip works for sot-23. for d(2)pak, you can use a bigger hotter iron.i use a 10x jewelers loup for inspection
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Hi Russell,
I use the German flux paste - see the picture. Something pretty similar in Mouser stock:
>NO CLEAN FLUX PASTE<
With regards to the FETs - good point. I think, I will have to remove a couple of the output plugs to be able to use some lower angle while soldering them, just to have more "massive" contact with the iron. I use a regulated-temperature iron, so normally, if I slightly increase it - it's enough for soldering such "areas".
Cheers,
Valery
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Good to know - thank you
Yes, this is exactly the National Association of Broadcasters. I am a video-encoding equipment developer and manufacturer - noisypeak. Five international partners are showing our products - have to oversee how it goes and support them in the meetings when necessary. Actually, I was not going to participate NAB show this year - preparing to the next year show - but too many companies are willing to show our gear, so it was the "last minute" decision to go
Although, I like to be in Vegas from time to time - no complains I have also got a pretty good loup, the bigger iron - would be good to have for bigger parts, will probably buy one soon.
Cheers,
Valery
Attachments
Hi Sam, it's possible to modify the OPS for N-channel only - I will drop the schematic update - but it will slightly suffer from additional distortion - not too much though, as the front-end is a relatively high loop gain one.
Cheers,
Valery
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