rwagter said:
I would worry about the pcb. Will it stand 10 - 20A ?
Any voltage drop due to trace resistance?
Perhaps Nelson Pass can enlighten us how their rectifier is implemented in de AX amplifier:
hardwired
on PCB
and when they are on a PCB, what is the traces thickness....
Ralph
hardwired
on PCB
and when they are on a PCB, what is the traces thickness....
Ralph
This one here looks even single sided. 
You may calculate the effective lead diameter by yourself.
Copper coating thickness is usually 35µm. Just measure the width....
You may calculate the effective lead diameter by yourself.
Copper coating thickness is usually 35µm. Just measure the width....
It's dubble-side:
componentside
solderside:
you will also noticed broad copper traces for the diodes
for more info:
http://home.swipnet.se/~w-50719/hifi/rfb01/
componentside
An externally hosted image should be here but it was not working when we last tested it.
solderside:
An externally hosted image should be here but it was not working when we last tested it.
you will also noticed broad copper traces for the diodes
for more info:
http://home.swipnet.se/~w-50719/hifi/rfb01/
UrSv said:
You are right ofcourse. I still believe they're going to be
depends on how he intends to configure the amp; total bias, number of bridges etc. I just saw AX together with that sexy little pcb and disliked the abuse. I would rather use it in a GC/class AB amp, where it seems more in place. I think construction of AX should be more industrial/heavy duty. Put the rectifiers on the main sinks and be happy 😉
Ralph, I understand your concern here but I think you must state what you need at least in terms of diodes and their rating, cooling and what the "duty cycle" (music or class A) is. With chosen heatsink profile KS35 Austerlitz, you will have from 9-13 deg / Watt at 5 W. This means total losses of 20 W.
If you intend to use the bridge in continuous use at 8-10 A or more you must have better cooling.
The pcb I have made is intentend for "audio" use, not really class A at 8-10 A.
If you intend to use the bridge in continuous use at 8-10 A or more you must have better cooling.
The pcb I have made is intentend for "audio" use, not really class A at 8-10 A.
UrSv said:
We use 4 of them, and yes, this reduces the dissipation for each,
and as the pair is on the same die, we don't worry about
current hogging between them.
Also the copper we use as a standard is 3 oz. If we need less
resistance, we use wider traces for the most part.
I have an power amp on the table also with such diodes, but unfortunately with removed type No face - check out last images from post #1 under
https://www.diyaudio.com/community/...ier-for-horch-3-0s-and-threshold-4000.379674/
The capacitors behind the rectifier are 47mF/63V from Ft-cap. The same amp model without the suffix "s" use a usual power bridge with type No KBPC50 with four integrated diodes and 500A peak forward (surge non repetitive) current and 50A average forward current. The right replacement in ultra fast version therefore is from my view this type due the same peak current value:
https://pdf1.alldatasheet.com/datasheet-pdf/view/22167/STMICROELECTRONICS/BYV52-200.htmlUnfortunately there is no enough space for a TO247 outline.
Are there any compatible choices in TO220 outline ?
This one are not suited:
https://www.onsemi.com/pdf/datasheet/mur1520-d.pdf (MUR15xx, 200A)
https://www.st.com/resource/en/datasheet/CD00000692.pdf (BYV99-200 200A, Pass-Recom.)
https://www.onsemi.com/pdf/datasheet/mur820-d.pdf (MUR8xx 100A, recom. sjostromaudio)
https://www.onsemi.com/pdf/datasheet/mur3020wt-d.pdf (MUR3020 100A recom. sjostromaudio)
check out the prepared units as follow:
https://sjostromaudio.com/pages/ind...-the-high-current-ultra-fast-rectifier-bridge
https://sjostromaudio.com/pages/ind...rfb01-the-ultra-fast-rectifier-bridge?start=1
https://web.archive.org/web/20040426140918/http://home.swipnet.se/~w-50719/hifi/rfb01/
I think, 200A peak current are not enough for this used capacitor values.
Thank you very much.
according the attached PDF is the use of high speed resp. ultra fast diode only an advantage if a suitable snubber network has been provided in parallel with the secondary winding of the mains transformer.
As conclusion I read this:
A 1R + 2C snubber directly across the secondary completely eliminated ringing in every case
But it remains unclear for me, however, whether this also applies to strongly fluctuating current consumption (as usual with class AB power amplifiers).
As conclusion I read this:
A 1R + 2C snubber directly across the secondary completely eliminated ringing in every case
But it remains unclear for me, however, whether this also applies to strongly fluctuating current consumption (as usual with class AB power amplifiers).
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