I have a question, is it posible to use the CLI if the J-link debugger is on the J2 port? Or is there another way to obtain the information on the J2 whitout using the CLI?
Yes that is possible.
J19 combines the JTAG debugger pins together with the UART pins, the UART pins are needed for the CLI.
There is a DCD-LZ breakout board which lets you connect your JTAG debugger to the JTAG debugger pins (like J2) of that breakout board and separates the UART to FTDI pinout.
This could be connected to J19 of the BMS.
See https://nxp.gitbook.io/hovergames/rddrone-fmuk66/connectors/debug-interface-dcd-lz/dcd-lz-breakout-b... for more detail on the breakout board.
Connector J2 is only a 10 pins JTAG connector, without UART pins.
You could use J2 to program/debug the board and use J19 for the CLI.
As an alternative to that, connector J21 has another UART bus on it.
Since the code is publicly available and it uses the NuttX RTOS, it could easily be changed in using the other UART bus for the CLI.
You could select LPUART0 as serial console in the menuconfig of NuttX (in Device Drivers -> Serial Driver Support -> Serial console).
So then you could use J2 for programming/debugging and J21 for the CLI if you configure it.
We are working with solar drone which requires a lot of power.
This product seems very nice but i am confused on the maximum rating. We have 6s configuration Lipo battery which is 22 volt, and the motor can require a huge burst current and continuous current(90A for minutes). I see that the maximum rating for this is 90A DC, Is this value continuous maximum rating or burst maximum rating. What is the burst current and time limit for the burst current. Can you please suggest me which can be better for me this one or the other BMS FRDM33772BSPIEVB.
Hope i get a very fast reply.
The FRDM33772BSPIEVB is an evaluation board for the battery cell controller. This is without microcontroller, switches, safety measures and etc.
The RDDRONE-BMS772 is a mobile robotics reference design including microcontroller, power switch, (working and available) example software, hardware overcurrent circuit and more.
For more information about the RDDRONE-BMS772 see: https://nxp.gitbook.io/rddrone-bms772/
For the example software see: https://github.com/NXPHoverGames/RDDRONE-BMS772
The RDDRONE-BMS772 as populated is rated for 60A continues DC current.
With 4 pairs of MOSFETs and 4 heatsinks it is rated at 90A maximum DC current (continues) and this includes the layout and copper used.
On the RDDRONE-BMS772 there is a hardware overcurrent circuit at 545A which will act within 20us.
Which means a peak current of 545A is allowed for 20us without damaging the board.
Higher currents or currents for a longer amount of time might be possible, but has not been tested.
Going over the maximum rated currents or the specified time will be of own risk.
Keep in mind batteries should always be handled with care.
Due to the chip shortage the PSMNR70-30YLH mosfet is no more available in the market. What to do with that, is there any other mosfet we can use with that model. Please reply me soon as we need this product as soon as possible.
Yes - sorry to hear that. I also looked, and you are correct, there doesn't seem to be global availability. This is an active and good part, it is just caught up in the global chip shortage.
Here are some (not so great) options:
- Contact Nexperia directly. You only need a few correct? Sometimes there are samples they have on hand.
- Look through Nexperia.com for close alternatives?
- Buy an additional BMS-772 and take the parts off one to add to the other?
The BMS772 does the self balancing. You will need to control the overall current provided to charge the battery. You should also provide some power steering/isolation otherwise with the two batteries in parallel, the higher charged one will attempt to charge the lower charged one.
Also - what is not clear above - are you making one pack or two separate pluggable packs. You CAN parallel individual cells in one large one (and use a single BMS) if you wish, but that does not seem to be how you have described it. So one BMS per pack is needed.
The BMS is approximately the size of a 3S 4000mA/h hobby LiPo - Sorry i do not have exact dimensions.
we have a drone battery that consists of 2 x 7000mAh 6S lithium polymer batteries. These two packs are going to be connected in parallel to achieve 14000mAh 6S.
What I did is made a housing to incubate the two packs and connected them to a single 10 pin robust male connector and in the UAV size there is a female connector . The plan is to make the drone battery like cartridge so we can slide it in UAV to click in and go on and when battery need recharging we take out the cartridge and connect it to the charger with same pin type used on UAV. The question is are we able to use you BMS 772 to achieve a self balancing cartridge when recharging?
if so how would we do that? Do we need two boards or one only? And how to connect it to the batteries?
and what’s the dimensions of that board please?