Hello,
We have a custom design based on EMB1402 evaluation board, consisting of EMB1428 and EMB1499. This is used to charge discharge a stack of 2Volt batteries. The system functions(able to charge/discharge cells), but intermittently shows failures(fault codes 0x90, 0xB0, 0x70 & 0xC0) on some of the lowside cells( near to ground of the battery stack). The chip however recovers from the fault on subsequent charge/discharge command. For example, I have summarized below two cases when I am trying to discharge the first cell(from ground) on the battery stack.
Case 1(faulting initially, however recovering when discharge command is continuously issued every 4seconds):
| Time line (seconds) | Command | Fault code |
| 0 | discharge | 0xB0 |
| 4 | discharge | 0xA0(no fault) |
| 8 | discharge | 0xA0 |
| 12 | discharge | 0xA0 |
Case 2: (faulting every time. Discharge command issued discretely, followed with open all switches command)
| Time line (seconds) | Command | Fault code |
| 0 | discharge | 0xB0 |
| 4 | open all switches | |
| 5 | discharge | 0xB0 |
| 8 | open all switches | |
| 9 | discharge | 0xB0 |
| 12 | open all switches |
Similar behavior is observed while trying to charge the cells. The battery stack consists of 12, 2V cells. We use two EMB1428 each one driving its on EMB1499. Each EMB1428 drives 6 cells. The issue is always seen on EMB1428 connected to the lowside bank of the battery stack.
We have below questions regarding this issue.
Is this an expected behavior? If so, does the chip requires a warm up time for charging/discharging?
What is the reason for those faults(0x90, 0xB0, 0x70 and 0xC0) to show up intermittently?
Is it an indication of the part being stressed intermittently which eventually could damage it permanently?
Thanks
Brayan
