AutoQuad Forum

BLDC connection in progress.

Yes, those resistors have a common trace, I have actually flowed solder between the 2 resistors to make a more suitable connection. If you look very close you will see that their is a trace between the 2 resistors and that's the PWM connection you need. You could read with an ohmmeter between the two resistors and they are connected, that would prove your on the correct junction.

Using this board, can I connect it to a 2S Lipo and will it power my M4 without any changes to it?
Further if I had to use a Graupner external RX, which requires between 3.6V and 8.4V how should I power it?
I would like to avoid having to use an additional BEC as it would add weight.

Hi,

let me update the thread with more info now that the M4 production boards are available. Since the LiPo voltage detector is the main difference when using the M4 expansion board I will focus on this!
More details on the difference between the board is available in the Wiki http://autoquad.org/wiki/wiki/m4-microc ... functions/

Beta board (left) side-by-side with a V2 production board (right).
The easiest way to distingish between beta and production boards is by looking at the onboard DC-motor connections!

ATTENTION: Since the V2 boards were using a different receiver chip which is connected to the SPI interface the voltage divider on the expansion board MUST NOT be used! KEEP JP1 OPEN (0r3 M4 expansion boards only) WHEN USING THE EXPANSION BOARDS WITH V2 PRODUCTION boards!

The V2 production boards have an onboard LiPo voltage divider.

LiPo voltage divider pads on the V2 production version

I've added a JST S3B-ZR-SM4A-TF(LF)(SN) connector to this position (Digikey 455-1694-1-ND). You can also solder some wires directly or use another connector type of your choice.

JST S3B-ZR-SM4A-TF(LF)(SN) connector added to LiPo voltage connector pads

Adding the CAN connector (provided, JST S2B-ZR(LF)(SN), Digikey 455-1669-ND) and another ZH-series connector for the Spektrum sat (JST B3B-ZR-SM4-TF(LF)(SN), Digikey 455-1682-1-ND) finished the soldering job on the V2 board. All other signals were connected via the expansion connectors.

JST ZH-series connectors used for CAN (S2B-ZR(LF)(SN)) and Spektrum Sat (B3B-ZR-SM4-TF(LF)(SN)) connections

Hi Jörg,

and what is connected to the "JST S3B-ZR-SM4A-TF(LF)(SN) connector" for onboard LiPo voltage divider?
I could not find anything about it in the Wiki.

Adn this can be done with a 2S Lipo as well? I want to be sure, as I do not want to get my M4 barbecued