korben69 said:
This is a universal PS board, it will work well with F4 or similar amp where CRC filtering is implemented.
For such application only 4 big untagged caps and big untagged resistors are being used.
The tagged parts are for a different application: to make a board more versatile, I also included space for regulators in addition to passive filtering. In case the board will be used for a preamp, DAC, CDP, or some other purpose where high current demads are not required, one can install 3 pin regulators in place of the series resistors: LM78XX, LM2937, adjustable LM317, LT1086 and their negative counterparts all will work here. There is also enough space for regulator's heatsinking.
Once I receive the boards, I will post pics with all different applications.
Oh, sorry, I made a mistake - I used Vishay for the bridge rectifiers, not IXYS
Digikey # is GBPC3502A-ND
If you want to use IXYS (more expensive), you could try the 27A-600V like the one on this page:
http://www.partsconnexion.com/catalog/semiconductors.html
If the price for the 160VA and 330VA transformers is not too much, then get 2 of the 330VA and you'll be sure to have more than enough (although some people think you can never have enough).
I have a single 400VA ebay Antek transformer in my F4. If I build another one, I will use 300VA Plitron.
Digikey # is GBPC3502A-ND
If you want to use IXYS (more expensive), you could try the 27A-600V like the one on this page:
http://www.partsconnexion.com/catalog/semiconductors.html
If the price for the 160VA and 330VA transformers is not too much, then get 2 of the 330VA and you'll be sure to have more than enough (although some people think you can never have enough).
I have a single 400VA ebay Antek transformer in my F4. If I build another one, I will use 300VA Plitron.
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Re: W4 Boards
It will depend on the regulator type. It's best to check applications notes for each one; getting linked through digikey is probably the easiest way.
The claer mask boards are done locally, through this company: http://electrocircuit.com/ Recently, I started sourcing boards from China and quality is as good, the price is much lower though. That would be all blue mask boards.
jleaman said:
It will depend on the regulator type. It's best to check applications notes for each one; getting linked through digikey is probably the easiest way.
jamayfie said:
The claer mask boards are done locally, through this company: http://electrocircuit.com/ Recently, I started sourcing boards from China and quality is as good, the price is much lower though. That would be all blue mask boards.
Hi Peter & Twitchie,
Nice to read you, many thanks.
Thank you Peter for the explanation, your PCB is a general purpose PSU. I understand why I can't match all parts according to F4 service manual.
Twitchie, some news :
1° - Bridge rectifiers : I'm wondering about Faston MB508, 35A/800v, do you think they are oversized ?
2° - Transfos : I've ordered two pieces : 330Va - 2X18 - 2x9.16A - ca. 124x50 mm - 3.4Kg/unit. Hope they will sound good enough, if not I'll use them with UCD. Plitron is very expensive in Europe.
3° - I think to fill each PSU board with 2x(22000µF+47000µF), about 138000µF. Do you think it's enough ? Nelson uses 120000. Caps are BC's, T=85°, 051 & 056 series running 40v.
4° - Where do you think to source 2SK370 and 2SJ108 ? Do they need to be Idss matched ?
I'm still modifiing the BOM and will post it actualised soon.
Nice to read your input.
Have a nice day.
Nice to read you, many thanks.
Thank you Peter for the explanation, your PCB is a general purpose PSU. I understand why I can't match all parts according to F4 service manual.
Twitchie, some news :
1° - Bridge rectifiers : I'm wondering about Faston MB508, 35A/800v, do you think they are oversized ?
2° - Transfos : I've ordered two pieces : 330Va - 2X18 - 2x9.16A - ca. 124x50 mm - 3.4Kg/unit. Hope they will sound good enough, if not I'll use them with UCD. Plitron is very expensive in Europe.
3° - I think to fill each PSU board with 2x(22000µF+47000µF), about 138000µF. Do you think it's enough ? Nelson uses 120000. Caps are BC's, T=85°, 051 & 056 series running 40v.
4° - Where do you think to source 2SK370 and 2SJ108 ? Do they need to be Idss matched ?
I'm still modifiing the BOM and will post it actualised soon.
Nice to read your input.
Have a nice day.
RDK845, Peter says, Post #143
"When I receive the boards, the payment info will be posted. There should be enough for everybody. No need to contact me now."
No one to give me an answer for my question about Thermistor CL60 type ? As far as I know, thermistor is used for thermal purpose, but in this case what is this part intended to do ? (yes newbie)
Is there someone to validate my BOM ?
"When I receive the boards, the payment info will be posted. There should be enough for everybody. No need to contact me now."
No one to give me an answer for my question about Thermistor CL60 type ? As far as I know, thermistor is used for thermal purpose, but in this case what is this part intended to do ? (yes newbie)
Is there someone to validate my BOM ?
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Joined 2002
korben69 said:RDK845, Peter says, Post #143
"When I receive the boards, the payment info will be posted. There should be enough for everybody. No need to contact me now."
No one to give me an answer for my question about Thermistor CL60 type ? As far as I know, thermistor is used for thermal purpose, but in this case what is this part intended to do ? (yes newbie)
Is there someone to validate my BOM ?
The Thermistor is to limit the time of the inrush current. Instead of it all being rushed in 100% it allows the current to be slowed down for a few seconds when turning on a power amp, sometimes you use a few of them depending on the size of the amplifier.
Jase
CL-60 is a NTC Thermistor. NTC = Negative Thermal Coefficent, means when its temperature is higher, the resistance will be lower. For CL-60, at 25 deg. C, its resistance is 10 ohm. When current passes through it, its temperature will rise and the resistance will decrease. If a steady current of 5A is passing through it, it may get pretty hot and the resistance may come down to 0.18 ohm.
When a power supply with a lot of capacitance is turned on, a very high current is required from the main to charge the capacitors and this will blow the fuse unless a big one is used. By putting a NTC thermistor in series with the main supply, the start-up current can be limited and the effect of the added resistance will be small when the current is steady.
You can download a data sheet in .pdf format for GE CL series from here:
http://www.alliedelec.com/Images/Pr...ture-Sensing_Actives-and-Passives_8370011.pdf
Usually you need one for each transformer. About how to choose the type of thermistor, you select by choosing the max. steady current and the resistance at 25 C and the resistance with load.
When a power supply with a lot of capacitance is turned on, a very high current is required from the main to charge the capacitors and this will blow the fuse unless a big one is used. By putting a NTC thermistor in series with the main supply, the start-up current can be limited and the effect of the added resistance will be small when the current is steady.
You can download a data sheet in .pdf format for GE CL series from here:
http://www.alliedelec.com/Images/Pr...ture-Sensing_Actives-and-Passives_8370011.pdf
Usually you need one for each transformer. About how to choose the type of thermistor, you select by choosing the max. steady current and the resistance at 25 C and the resistance with load.
Thank you RoboMan for the usefull informations and explanations.
I've found another part, GE one's seems not to be available.
Link to the manufacturer product : http://www.ametherm.com/Inrush_Current/inrush_current_data_sheets.htm
The ref N° SL18 or SL22 seems to be Ok for 10R with 5A, quite similar to CL-60.
I've found another part, GE one's seems not to be available.
Link to the manufacturer product : http://www.ametherm.com/Inrush_Current/inrush_current_data_sheets.htm
The ref N° SL18 or SL22 seems to be Ok for 10R with 5A, quite similar to CL-60.
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Joined 2002
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