I'm pleased to announce the reproduction of Amiga 4000 T PCBs.
These are 6 layer boards identical in functionality to the A4000T Rev 4 motherboard PCBs. I will provide full BOM for the project in Excel sheet with component values and locations. But please understand that I only provide the PCB set, component list, and a some build tips. I CANNOT not provide support for building or where to get the components etc..
I don't plan to have further batches at the moment, will decide after the first batch (if there is enough interest). So I advise to get your board while you can.
Also important to note that this is NOT a bedroom/hobby/home made design. This has been done by a professional PCB design firm. So the design, layout and routing is properly tested against PCB manufacturing standards and design verification rules, following industry practices, such as considering heat, signal propagation, noise and EMI, and correct ground and voltage layers. This is as close as you can get to actually owning an original A4000T motherboard PCB in 2020!
The boards come as sets, one set includes 1 of each PCB. This is what you get:
- motherboard PCB- video module PCB- disk module PCB- ports module PCB- full BOM in Excel format- layout pictures with component marking in PDF- build tips I learned during prototyping and testingThe board have been extensively tested in 3 stages:
- During PCB design (DRC rules, against original schematics etc..)- During manufacturing (complete electrical test with test rig)- One fully working prototype has been built to verify all functionality. Tested all functionality, including (but not limited to) ChipRAM, fastRAM, ROMs, RTC, KB, mouse, ports, IDE, SCSI, Zorro, video and PC slots as well. SCSI was tested with an internal drive copying between CF IDE and a SCSI HDD for hours.Some pictures of the different design and verification stages below.
The PCBs came out very nice, almost 100% identical to the original boards:
First all the passive components were populated on the bottom side, then top side along with all the TTL chips, and some QFPs. Basically all components were mounted at this stage that I could hot air mount relatively easily:
At the next stage I've mounted most of the large(r) PLCC custom chips, and some other components and connectors for minimum power-up test, so I could check that key system signals (clocks, supply voltages, video sync etc..) are OK, and basic functionality of the system (video out, ROM and chipRAM access) is sufficient to continue: (A special greetings shout-out to John 'Chucky' Hertell the creator of Amiga DiagROM!)
After this I've mounted most of the remaining connectors and components, in the end I have decided to desolder and put all the custom PLCC chips on socket, even though they were tested before soldering on the board. This happened to be a very good decision (for prototyping) as it's much easier to check and diagnose system signals if chips can be swapped out quickly.
Here are few pictures of the final stage of the test board, notice that the video module soldering is not as good as the rest as I did it in a 'hurry' without a stencil. But it'll do for prototype I think
Videos of the finished board in action: