I am planning to use a Beaglebone Blue in a drone that I am building. The drone motors need a 4s battery which runs at 14.8V however the connector for a battery on the Beaglebone Blue seems to only support a 2s battery which operates at 7.4V. How would you recommend running the Beaglebone Blue off a 4s battery? If needed we are able to solder components together.
Are you expecting to also charge the battery using the Beaglebone Blue? If not, why not connect the battery to the DC jack input?
Graham
I am a bit unsure on how to connect the 4s battery to the dc jack. It is using the battery connector found on this jack https://www.unmannedtechshop.co.uk/product/tattu-1800mah-14-8v-45c-4s1p-lipo-battery-pack/. Is there some component I can by which I can solder on the end of the battery leads to go to a dc jack I can connect to the beaglebone blue?
The charge balance connectors are typically JST PH connectors on a 0.1" pitch (though might be 2mm - it think that’s JST XH). They bring out the two ends of the battery pack (the same as the high current connector) and every junction between cells. So the 2s charger on the BBBlue has 2+1 pins and the 4s connector on your battery has 2+3 pins.
The outer pins, if connected to the BBBlue, will provide 14.8 - 16.8V and this might be OK to power the BB although it will not be able to charge it correctly using the charge balance wiring. I’m not entirely certain that it will be OK - the DC jack is rated to 18V but the charge connector is only expected to supply 8.4V to the pack and may not tolerate the 4s pack.
Since you aren’t able to charge it that I would think it would be safer to use the DC jack as Graham says, though you will need to fix the connector in as they won’t stand much vibration and it’s likely to fall out during flight.
You will need a wiring harness to connect the heavy current output from the lipo pack to the motor controllers. You may be able to buy this ready made and add a wire to supply power to the BBBlue (it might already have a controller power connection, or the speed controllers might have a 5V output for it). If you make it up from individual connectors, the part for the battery pack is called a TX60 (or the larger TX80) and is easily available from ebay or quadcopter supply sources. The same connector is probably used on the motor controllers, or they might be fitted with one of the other standards. Quite often they have no connectors fitted as there are a number of different options alongside TX60.
The battery at the link you provided has a TX60 connector for the power leads. I do not know where you are located but you could order the following from Pololu and make a cable that splits the power with a pair (red and black) going to a new TX60 connector which mates with your drone motors and the other pair (Red and black) going to the DC barrel Plug. The center pin is the positive (Red).
DC Barrel Plug – part 2448 - https://www.pololu.com/product/2448
XT60 Connector – part 2158 or 2175 - https://www.pololu.com/product/2175
Graham