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As a part of our work with developing eVTOLs in the Hellaplanes, recently I designed a PCB that greatly simplifies connecting the mini REVO flight controllers for use in multirotors and winged aircraft. It provides two separate 5V 3A supplies, one for the receiver and flight controller (and other devices such as GPS, OPLINK, and OSD), the other for servos. If you use BESC, it can be used in place of the second 5v supply. Up to 6s battery input.
We found the extra power from servos could occasionally glitch the flight controller when they were grouped together - this prevents that.
It also has a socket for OSD, and some simple circuitry for our wing switch.
We normally use either cPPM serial or s.bus serial connections to receivers - this allows either up to 11 or 12 PWM outputs from the flight controller.
If anyone is interested, we can make some available for a modest cost.

karla

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Re: Power and signal distribution PCB for mini Revo flight controllers
« Reply #1 on: August 02, 2022, 04:02:00 am »
Good!
Yes, I am interested.
Its really a tough soldering job to get the servos connected and also the Amp limitations.
Can you give more specifications like size and weight?
Best
Karl

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Re: Power and signal distribution PCB for mini Revo flight controllers
« Reply #2 on: August 02, 2022, 06:26:21 pm »
Weight: 52g
Size: 35mm W x 145mm L x 30mm H - not including the wires out the back.
The servo area has 5V tied together as one wire (heavy trace on front and back)
The board itself has a single sided ground plane, also connected to servo ground.
1000uf bypass on servo area
5V 3A for servo area (but can be removed and use BESC power)
Separate 5V 3A for rcvr, fc, OSD, OPLINK, GPS, etc - 100uf bypass on this line
Up to 6S power input to the 2 linear voltage regulators - these parts also have overcurrent and overheat protection
Heat sink with 5V fan
OSD connector is designed to work with the minim OSD
Wing sensor is a 1k resistor pull to to 3.3V, designed to connect to a switch and use the Pwr Sens input we use for bimode (our custom version of Librepilot with 2 sets of mixers, plus a few other options)

Note, the servo connector area and power areas are separate - we can cut off the servo connect area and it can be used without the rest, or just re-positioned.  Also the 2nd 5V for the servos does not have to be included to save weight.

In general we have been using the mini REVO fc and using the 8 pin to 6 sets of 3 pin servo connectors (two times 6 = 12 outputs possible) to connect to this board.

S.bus allows all 12 to be used as outputs. cPPM needs one channel for the serial input, so 11 channels of output available.

Let me know what options you want and I can quote a price.

karla

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Re: Power and signal distribution PCB for mini Revo flight controllers
« Reply #3 on: August 03, 2022, 02:40:32 am »
Quote
Note, the servo connector area and power areas are separate - we can cut off the servo connect area and it can be used without the rest, or just re-positioned.  Also the 2nd 5V for the servos does not have to be included to save weight.

Let me know what options you want and I can quote a price.

Well, lets try two with the full board and two with only the servo area.
Would be interesting of you can post a some pictures with the mini Revo and servos etc connected.

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Re: Power and signal distribution PCB for mini Revo flight controllers
« Reply #4 on: August 05, 2022, 07:47:00 pm »
Here's a pix of one installed.
The mini Revo is on the bottom.
Two sets of 6 connectors - outputs plug in on the lower left of the PCB. I usually order them from 1-12 starting at the bottom.
Note ONLY the outputs connect to anything - power and ground are not connected from the mini REVO on the connector pin array.
The cPPM input, plus power gets connected to the bind input on the rcvr. (white/red/blk)
Power to the rcvr and then to the min-Revo comes from the 3 pin (only two used) connector (blk/green) middle left of the flitebrd.
All the servos and motor esc cables are on the bottom right.
Battery power to the flitebrd comes from the red (+) cable upper left, and blk (- under). I usually put 3mm connectors on these to make it easier to connect to whatever. I can supply both ends with 3mm, or just leave these as stubs.
Enclosed photo and schematic. Not shown on schematic is 2nd 5v output. This is a separate 5v regulator with +5/gnd connected to a 3 pin servo cable, that plugs into the end of the chain of servo connectors (see original photo).
There are 3 extra 3 pin connectors on the servo chain to allow for the power input (if used), and 2 other devices that may need power. Normally one also has the 1000uf cap connected also.


karla

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Re: Power and signal distribution PCB for mini Revo flight controllers
« Reply #5 on: August 06, 2022, 04:21:20 am »
thank you.

Is the BEC to the far right in the picture supplying both the two +5V sources?
or you have another BEC?


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Re: Power and signal distribution PCB for mini Revo flight controllers
« Reply #6 on: August 06, 2022, 08:35:23 pm »
Yes. There is a single heat sink+fan but underneath are two LM1085 5V 3A linear regulators. The left most one is used for the rcvr, flight controller, etc power. The right most one for servos, if there is no power supplied by the ESCs.

karla

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Re: Power and signal distribution PCB for mini Revo flight controllers
« Reply #7 on: August 07, 2022, 02:39:08 am »
Okay, thank you.

I realise my need is a very small number and maybe not worth the trouble to make it.
Can you give a price for 2 units that includes the heat sink+fan plus the two LM1085 5V 3A linear regulators?
In addition to that I am interested in two small(er) units with only with the servo pin part.
That will be installed in helicopters and need to be small but don't need gps, mags, osd etc

Maybe we can continue discussion in PMs.
Regards
Karl

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Re: Power and signal distribution PCB for mini Revo flight controllers
« Reply #8 on: August 07, 2022, 05:53:47 pm »
No problem on small order. I did this knowing it would be small numbers - just want to help out fellow enthusiasts.
I'm planning on making up 8 or so units - at least 2 with just servo pin blocks for you.
I have a gal who does assembly for us free-lance and does impeccable work and is reasonably cheap - $30/hr
May take a week to finish if that's ok. After I know how much she'll charge I'll have a better idea how much it costs.
I'll just charge her cost plus parts cost & shipping.

karla

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Re: Power and signal distribution PCB for mini Revo flight controllers
« Reply #9 on: August 08, 2022, 02:13:07 am »
Thats fine, thank you!
No hurry.
Regards
Karl