Based on a recent discussion with @German_io I looked further into a very high powered, yet DIY-able board. This is the power stage prototype of such a board, using discrete 300A/100V Infineon IPT015N10N5 MOSFETs paired up with Microchip Tech MCP14700-E/MF discrete drivers, high-power current sense resistors and INA225 current sensors.
As designed, the 4-layer PCB is 5x5cm and can carry continuous 30A without any issues, even though the MOSFETs are rated up to 300A continuous. The 1oz limit of JLC cuts the power to 30A before you overheat and melt the board itself.
I’ve ordered the board, will post progress here once fabbed. If the design works, perhaps this could be the base of an ultra-high power board.
Yes, I went through great pain to ensure as many basic parts in stock as possible. These days this is really hard.
These are 10uF / 50V basic SMD thin film capacitors, and two 100nF snubbers on both sides. Total about 500uF. This is just for testing, the final design would have a very large external electrolytic capacitor.
The voltage is restricted to 25V via TVS, that black thing on top, else it may damage the rest of the components which are restricted to 30v and pop the 50V capacitors.
The Jackhammer was delivered, tested and passed the most basic test of generating the signals and turning a very simple test motor in open loop velocity at 12V / 1A, without anything blowing up.
I’m not getting excited yet, there is a long road ahead. Many things could go wrong.
I’m off to Vegas for the New Year, but when I get back, if I still have not gambled my R&D budget, will continue testing.
By the end of this week I’ll get it to a point to fabricate.
Added the entire MCU section, CANBUS, SPI, HALL sensors, Serial, NTC thermistor and a bunch of LEDs for the spare pins for people to use for visual debugging. Plus 5V for an external fan.
I’m going away with the USB, instead you will need a separate UART debugger probe to test, this is not a hobby board anymore.
Biggest change is I went for ultra-fast Hall inline current sensors, no sense resistors / sense amplifier. This also removes the common mode voltage limit. That way, I could get the board up to 100V if properly configured with the right components.
Also, the board has split power and control ground planes.
Goal is to be able to fab directly with JLC, out of the box, without any post-production work, except soldering the leads and may be connectors.
The board as of now is 5cm X 7cm (50x70mm). I’m planning to add as an extra module reverse current protection, as well as some more safety features and buffer capacitance, however, these are optional. They will also increase the cost. Right now the board is about $100. The board will need a heat sink for high current.
Update. There is something really scary happening right now. Overnight even basic resistors, capacitors, LDOs, LEDs, MCUs, have all disappeared. This is not someone putting an order, this is the factories hiding capacity and redirecting to internal consumption.
That’s really bad. I stop working on any design until this clears up.
Hope that things will get fixed soon.
Sayonara.
This is the BOM for my board, yesterday only the MOSFETs were out of stock, look today.
I must have broken the record for PCB redesign, I pretty much changed everything to get it in stock.
My beautiful board ended up butchered, ugly and sad, like all that garbage you buy from Alibaba for $20 and then it breaks in a month. I designed a Cadillac with Kia parts.
Tragic.
I renamed the board to HACKJAMMER. Shame.
Well, the hacky board is in production, let’s see what happens.
Only the CAN controller could not be replaced, so I left that out.
I am at a loss what to do, so at that point I’m only experimenting with random things until situation stabilizes. My educated guess is that JLC is exploiting the situation and hiding inventory for long term customers and allowing only expensive parts to low volume customers to maximize profits.
It’s basic supply / demand.
There is a big industry convention in San Francisco (Photonics West), I’ll visit in two weeks, and talk to ST Micro, may be I’ll get some information.
CAN transceivers are in stock. Some of the controllers, too.
Yesterday JLC had a massive database overhaul, may be you need to check later today.
I have my own database connected to JLC which does not use the web site. Using the web site is a crapshoot. I use the web site only for quick checks. Also, you need to talk to JLC directly for more complicated orders.
There are many people who watch the inventory very closely, and the moment the correct components are in stock, they are very quick to put in the orders. It’s a Wild West out there now.