Choke Loaded Tokin SIT Follower PCB
Some people like cross-work puzzles. Others prefer Sudoku. I like playing with LTSpice and more recently, Kicad. So to practise and get better at Kicad, my latest project is a PCB for my choke loaded 2SK180 follower. Since this is a new pcb design, I used this opportunity to change the power from V+ to V-, to be able to connect the SIT drain to ground. My current iteration of the amplifier with its V+ supply is actually quiet with my 103dB speakers. What noise that may be present is not audible. That could be because the CLC power supply has very low ripple, there is very little noise to past through the 2SK180. But this is diy, so I am doing this not because I need to do it, but I am doing this for the fun of it.
Schematics and PCB images are attached.
Note that my amplifier uses Tokin 2SK180, but other Tokin SITS such as the THF-51S or 2SK182ES can also be used. The same operating points can be used. The more adventurous can play around with Vds and Iq and choose their own operating points.
Some people like cross-work puzzles. Others prefer Sudoku. I like playing with LTSpice and more recently, Kicad. So to practise and get better at Kicad, my latest project is a PCB for my choke loaded 2SK180 follower. Since this is a new pcb design, I used this opportunity to change the power from V+ to V-, to be able to connect the SIT drain to ground. My current iteration of the amplifier with its V+ supply is actually quiet with my 103dB speakers. What noise that may be present is not audible. That could be because the CLC power supply has very low ripple, there is very little noise to past through the 2SK180. But this is diy, so I am doing this not because I need to do it, but I am doing this for the fun of it.
Schematics and PCB images are attached.
Note that my amplifier uses Tokin 2SK180, but other Tokin SITS such as the THF-51S or 2SK182ES can also be used. The same operating points can be used. The more adventurous can play around with Vds and Iq and choose their own operating points.
Attachments
Hi Ben, did you try the DN2540 buffered version? Just asking because you could incorporate it into the board and bypass it if it’s not used. I’m doing this with my build. I’m just being slow on the build for this one.Choke Loaded Tokin SIT Follower PCB
Some people like cross-work puzzles. Others prefer Sudoku. I like playing with LTSpice and more recently, Kicad. So to practise and get better at Kicad, my latest project is a PCB for my choke loaded 2SK180 follower. Since this is a new pcb design, I used this opportunity to change the power from V+ to V-, to be able to connect the SIT drain to ground. My current iteration of the amplifier with its V+ supply is actually quiet with my 103dB speakers. What noise that may be present is not audible. That could be because the CLC power supply has very low ripple, there is very little noise to past through the 2SK180. But this is diy, so I am doing this not because I need to do it, but I am doing this for the fun of it.
Schematics and PCB images are attached.
Note that my amplifier uses Tokin 2SK180, but other Tokin SITS such as the THF-51S or 2SK182ES can also be used. The same operating points can be used. The more adventurous can play around with Vds and Iq and choose their own operating points.
Attachments
Hi Monk55, I will mostly likely use JLCPCB. However I am still reviewing and checking, correcting a few mistakes, and tweaking.
Hi Botte, No, I have not considered adding an input buffer since I do not need it. I don't want to make the board larger to accommodate a buffer and then not use it. Is your buffer on a separate board? Are you using a DN2540 for CCS? Are you feeding V- to the output board?
Hi Botte, No, I have not considered adding an input buffer since I do not need it. I don't want to make the board larger to accommodate a buffer and then not use it. Is your buffer on a separate board? Are you using a DN2540 for CCS? Are you feeding V- to the output board?
A couple of corrections and a bit of tweaking, added a LED, and I think it's close to being done. I'll let it sit for a few days and then I may be ordering PCBs.
Attachments
English please.
The gain required depends on the voltage of your source.
For the amplifier to output 25W into 8 Ohm, you need to input a signal of about 17Vrms to the amplifier. This takes into account that the full voltage input is not outputted by the amplifier. However most people don't listen to music with their amplifier outputting its maximum power continually. So in reality, you could probably get by with much less voltage output from your preamp, especially if your speakers are relatively sensitive.
Well I really do enjoy sending other peoples great Gerbers to JLCPCB, it makes me feel a little bit more serious diy-er. And I have this great amp in point to point version on a kitchen board, great sound but could be a more orderly and safer build. So I will order these PCBs when Ben is satisfied with it and makes the Gerbers available....
So you are welcome to join forces!
Leo