I have lately had 3, possibly 4, projects in the pipeline.
One is this motor drive, which has been internally called ACE-NX.
Key ideas here:
- No more "ESC" stuff with the inline wiring, caps sticking off the end of the board, shrink wrap, ... Instead, this takes a more ground vehicle/robotics/industrial approach. Mounting holes, like the S-Core board. Phases and DC input wires emerge vertically out of the board. Cap cans are also mounted vertically through-hole (note big pads for thermal contact to solder those, since there is no relief on the pads for impedance purposes).
- The idea with the packaging of this is to design it into future blasters rather than to fit existing ones, since now there hasn't even been a supposition of using off the shelf drone ESCs in blasters for over a year and that paradigm is kinda meh.
- Return to the "sandwich inverter" bus structure and power device layout, from the ACE-LC1 and Protoverter.
- Set up to be easily built as multi-voltage. This uses a 60V rated buck converter (LMR16006) to drop logic power off the bus. The powerstage can be populated with various 60V LFPAK56 devices to correspond and so forth for the DC link caps; hence this can support bus voltages up to approximately 10S, conservatively. The buswork is also very beefy, and this board would make a good super-low RDs(on) current monster using fets like the PSMN0R9.
- Infineon 6EDL04 gate driver.
- Has the S-Core style logic power input de-sagger/negative transient remover, albeit with a smaller 8mm cap footprint for the reservoir cap to save some space.
- Has (optional) TVS across the bus at the power supply section to further safeguard the first DC/DC converter from spikes.
- 12V gate drive level derived from 5V rail by AP3012 boost converter. Typical transient-robust approach to buck then boost, though I probably could get away with 2 parallel bucks instead, given the input filter on this thing.
- Standard ICSP header, just plug in a ISP device and flash, no soldering to pads.
This was my first crack at it after being rusty and not designing any boards for a while. Also, I used minimum 0805 and some way larger trace/space than I could have, plus the big 20x40mil vias that I always used in my past boards like the LC2. Also, I tried out keeping roughly the bs_nfet pinouts and not shuffling my MCU pin assignments around to get the lane between that and the driver to work better hence a lot of contortion going on under the MCU. Still, it ended up at 25x62mm, the same width and shorter than a fully dressed LC2 with cap and wiring. That's promising, at least, but I will nevertheless set this file aside and cook one more PCB before this is over.
Also worth mentioning the improved LFPAK footprints I'm trying out with this round (for hand soldering, not reflow obviously) and the return of the Afro's familiar blinkenlights. Anyway, this sort of thing is the future for my blasters, pretty much.
Next one, a simple discrete drive ESC style one with a 3.3mm (LFPAK33) powerstage, all 0603 except the Vcc bulk cap and bootstrap caps, SOT-89 linear reg. This should be a useful handy little thing. 18x40mm.
I made sure to use the MiniMELF compatible footprints for those
bootstrap diodes this time round, the glass ones are so much less boring than
SOD-123s. Also, Nexperia seems to have recently replaced the
PSMN2R4-30MLH[X] with a PSMN1R6 part, which if you dig the Nexperia FET
part number's logic, is a 1.6mohm nominal part. The 5x6mm device used in
the ACE-LC2 is 1.4 (Hell, most of the losses are switching and diode
conduction anyway at that point), and with the intended addition of solid
wire or bars down those completely-unmasked bus traces, there should be enough cooling on them that this
board can run all the usual 2205-ish motors without a hitch while also
being smaller than LC2, Afro, Spider and friends.
And the last: a display module for the S-Core.
Of course one route is the usual Arduino style thing with Chinese OLED modules or LCD and be all modern and graphicky, but that is... simultaneously way overkill for just a blaster, and not kill enough to be worthy of a blaster, so in usual DZ fashion I took a more old school/hi-rel/vaguely industrial route with 5 cells of 0.2" LED 7 segment driven by a string of 74HCS595 chips. These things are slated to plug into the programming header on the S-Core board, which conveniently has power, ground, and 3 pins usable as digital I/O during runtime on one connector and avoids tying up the other ADC capable GPIO expansion connector on the board. The data line is bidirectional for that user button. As to that, this board and its design probably warrants another post so I will save it for that.
The possible 4th project is to replace the LC2 with a 6EDL04 driven, switchmode logic power, version of the same sorta-thing. With 0603 and 10/10mil it should be possible. I already mocked up a take on it way back on here, so no big deal.
The 5th is more unknown. Maybe a single-board blaster solution, maybe a driver-equipped version of the Mini above... or a 2 channel version with switchmode logic power. Or maybe a battery protection/management module that I have been wanting to do.
