Active balancing with LT8584 and ADBMS6830B

I can answer questions related to ADBMS6830B. 

RobertJan said:

Is the LT8584 compatible with the ADBMS6830B?

No it is not directly compatible, we do not have a compatible IC from ADI that works with ABMS6830B. 

RobertJan said:

2. If they are compatible, are there reference schematics and function descriptions we can refer to when combining the two? Like referring to the ADBMS1818 datasheet which does contain a description of the communication.

Communication is different on both the device as ADBMS6830B uses isoSPI to communicate.

Thanks for clearing things up! Since we need SIL2/PLd, would the ADBMS1818 be a good choice? It has better availability and better pricing than the ADBMS6830B. Only thing I'm not sure about is if the 1818 has SIL2/PLd capabilities. I'm not very concerned about precision, sample speed and double ADC's. As long as the diagnostic coverage and MTTF are high enough to be able to pass SIL2/PLd if our hardware design is done correctly.

And would the ADBMS1816 be suitable, since we need only 16 cells. But the datasheet seems to be unavailable?

RobertJan said:

Thanks for clearing things up! Since we need SIL2/PLd, would the ADBMS1818 be a good choice? It has better availability and better pricing than the ADBMS6830B. Only thing I'm not sure about is if the 1818 has SIL2/PLd capabilities. I'm not very concerned about precision, sample speed and double ADC's. As long as the diagnostic coverage and MTTF are high enough to be able to pass SIL2/PLd if our hardware design is done correctly.

And would the ADBMS1816 be suitable, since we need only 16 cells. But the datasheet seems to be unavailable?

You can use either to meet SIL2/PLD safety. We do not qualify them for safety use, its is upto system designer to qualify the safety level.
Here is a quick comparison table i made for your reference;

Thanks for your reply and the detailed comparison table! Looks like we are losing some performance when switching to the 1818. Which is probably fine.

1. The 1818 states it supports synchronous cell and current measurements. This is a benefit over the 6830B? Or is this in general possible with an isoSPI bus with Analog Devices AFE's? We plan on combining the 1818 or the 6830B with the LTC2949 or the ADBMS2950B.

2. While having a look at the LT8584 to match it to the 1818, I noticed it can run in simple mode, with a simple on/off signal. This mode should in fact work for the 6830B with an external FET on the SN/SP pins, or on any passive balancing AFE, right? Or does the serial mode have so much advantages that it is not recommended to use the simple mode?

RobertJan said:

1. The 1818 states it supports synchronous cell and current measurements. This is a benefit over the 6830B? Or is this in general possible with an isoSPI bus with Analog Devices AFE's? We plan on combining the 1818 or the 6830B with the LTC2949 or the ADBMS2950B.

It is possible with ADBSM6830B too. If you are planning on using pack monitor i highly recommend using ADBMS6830B along with ADBMS2950B for the ease of software design and they work in the same daisy chain, ADBMS2950B has significant architectural changes which simplifies software design compared to LTC2949. 

RobertJan said:

2. While having a look at the LT8584 to match it to the 1818, I noticed it can run in simple mode, with a simple on/off signal. This mode should in fact work for the 6830B with an external FET on the SN/SP pins, or on any passive balancing AFE, right? Or does the serial mode have so much advantages that it is not recommended to use the simple mode?

I cannot comment on this with absolute surety as I dont support  the IC. Somebody else can confirm this if you post it as another question and tag the device. ADBMS6830B when balancing is enabled just shorts SP to SN pin through and internal FET, so if you use this as the signal you should be able to work with it.

I've made a new question regarding the LT8584. Since our goal has shifted back to the ADBMS6830B, I still have the question about the bypass capacitors on the SxP pins. On the forum I see some comments that 'in a newer version of the datasheet this will be fixed', suggesting that a newer datasheet has a more accurate description of the capacitors. For me, the 6830B datasheet seems to be really basic in comparison to other AD parts which suggests that a newer datasheet revision may be available or in development.

But the specific question:

Do we need these capacitors?

If we need them, do we need to match them to the S1P-S1N bypass capacitors? In the demo schematic, the SxP-SxP caps are matched to the SxN-SxP caps.