insulation/non-insulation pads...
Is there a rule that defines which devices need to be insulated and which ones are not. I read the Q Pads which states "Use where electrical insulation is not required". And I believe Sil Pads offer both.
http://rocky.digikey.com/WebLib/Berquist/Q3.pdf
I guess I could look up each device to find out but I was wondering if there was a rule of thumb to be used.
Stan
Is there a rule that defines which devices need to be insulated and which ones are not. I read the Q Pads which states "Use where electrical insulation is not required". And I believe Sil Pads offer both.
http://rocky.digikey.com/WebLib/Berquist/Q3.pdf
I guess I could look up each device to find out but I was wondering if there was a rule of thumb to be used.
Stan
Good pic on the devices,
I remember reading a thread on comparing the OPA627 to the AD810AR which comes in a SO8 only but Brown Dog makes this very cool SO8 to DIP8 adaptor for only $2.00 bucks ea.
http://cimarrontechnology.com/index.asp
I remember reading a thread on comparing the OPA627 to the AD810AR which comes in a SO8 only but Brown Dog makes this very cool SO8 to DIP8 adaptor for only $2.00 bucks ea.
http://cimarrontechnology.com/index.asp
Attachments
I will admit I am still in the building phase for my Aleph Mini, but for the to-247's I have some BER178-ND from Digi-Key and some 532-4180 from Mouser that I intend to try out. TO-220 pads are not big enough for a TO-247. Neither should break the bank.
Hopefully, being Saturday, my brain is not too far out of gear, but if you look at the Q-Pad 3 data sheet it gives the electrical volume resistivity, which together with the heat pad area will give you a resistance value. The cases of any components on the same metal surface will be electrically connected to that surface and each other by about that value of resistance. Might be OK for a single isolated component on an isolated piece of metal, but more likely will provide a conductive path from the case to ground and short the cases together.
I am somewhat new to the forum, but have seen how sensitive the heat sink issues have been in the past, so I hope this is helpful without starting any flames. But I would welcome helpful comments.
Hopefully, being Saturday, my brain is not too far out of gear, but if you look at the Q-Pad 3 data sheet it gives the electrical volume resistivity, which together with the heat pad area will give you a resistance value. The cases of any components on the same metal surface will be electrically connected to that surface and each other by about that value of resistance. Might be OK for a single isolated component on an isolated piece of metal, but more likely will provide a conductive path from the case to ground and short the cases together.
I am somewhat new to the forum, but have seen how sensitive the heat sink issues have been in the past, so I hope this is helpful without starting any flames. But I would welcome helpful comments.
Forgot to add this:
Volume resistivity is defined as the ratio of the dc voltage drop per unit thickness to the amount of current per unit area passing through the material. A basic material property, volume resistivity indicates how readily a material conducts electricity through the bulk of the material.
Might help with figuring out if you want to use the Q-3's.
Volume resistivity is defined as the ratio of the dc voltage drop per unit thickness to the amount of current per unit area passing through the material. A basic material property, volume resistivity indicates how readily a material conducts electricity through the bulk of the material.
Might help with figuring out if you want to use the Q-3's.
Banned
Joined 2002
Banned
Joined 2002
Use this sheet.. it is what im using.. No schematic that i know of..
http://www.diyamps.com/aleph/docs/miniALEPH-parts_list.xls
http://www.diyamps.com/aleph/docs/miniALEPH-parts_list.xls
For A30 schematic, I plan to use this ..... http://www.passlabs.com/downloads/old product/a30manr0.pdf
See page 16.
See page 16.
Banned
Joined 2002
Finished my new mini aleph last night,decided to go with the Mini first rather than the A30.Case from a old P3A no room for the transformer though, after two hours the temp of the sinks are fine so in the future I'll be increasing the bias. Running with a 300VA 12-0-12 tranny, rails +/- 16VDC,offset left 4.8mv right 12.4mv.
I can't believe how good this amp sounds after so little time, feelings of deep joy.
Many Thanks to all involved in this project, greatly appreciated.
What better its Friday as well,think I'll stay in tonight with a couple of bottles and enjoy some music.
Cheers
Bruce
I can't believe how good this amp sounds after so little time, feelings of deep joy.
Many Thanks to all involved in this project, greatly appreciated.
What better its Friday as well,think I'll stay in tonight with a couple of bottles and enjoy some music.
Cheers
Bruce
Attachments
Gents,
I powered my mini up last night and (after a little smoke
) she came up fine! I had soldered the legs on the 9610's together so I could manhandle the boards without blowing the fets with static. I forgot to cut the solder bridges out...need I go on!
Question, with 17.8v rails, how much power am I making? It sounds real nice on my old Infinity rs4b's in the garage and I am very impressed (and pleased with myself).
I will have plenty of pics to follow when it is cosmetically done but here is a preview. As you can see I will be able to bias those irf150's to my hearts content. This baby's gonna get some white oak accents and is my take on the original A30 design.
I powered my mini up last night and (after a little smoke
) she came up fine! I had soldered the legs on the 9610's together so I could manhandle the boards without blowing the fets with static. I forgot to cut the solder bridges out...need I go on!Question, with 17.8v rails, how much power am I making? It sounds real nice on my old Infinity rs4b's in the garage and I am very impressed (and pleased with myself).
I will have plenty of pics to follow when it is cosmetically done but here is a preview. As you can see I will be able to bias those irf150's to my hearts content. This baby's gonna get some white oak accents and is my take on the original A30 design.
Attachments
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.