BQ78350-R1: BQ78350-R1 - 0x2B HostFETControl command failure

Anton Kalinichenko

Part Number: BQ78350-R1
Other Parts Discussed in Thread: TMS320F28062,

Hello,

Recently I have faced to an issue executing 0x2B HostFETControl operation (TMS320F28062 is a host MCU). Symptoms is very likely as described in https://e2e.ti.com/support/power-management/f/196/p/537624/1959380# topic:

1. I2C speed is 100K. I2C communication is OK (There are several well running devices on the bus).

2. All other BQ78350-R1 commands are executed normally.

3. I run several experiments to put delays before, between and after pair of commands (0x2B, 0x97, 0x11 and 0x2B, 0x00 / 0x01) and that did not help.

4. For testing purposes I also left only HostFETControl commands in code to isolate it from other BQ78350-R1 commands. This did not help as well.

Unfortunately there is no solution in the topic pointed above - any ideas to fix this problem?

Best regards,

Anton

over 5 years ago

0 Matt Sunna over 5 years ago

TI__Guru* 81035 points

Hi Anton,

I'm not sure what is causing this issue, but I know this function can be tricky. The HostFETControl operates on a 4 second cycle. If the write is unsuccessful due to timing or intervening communication, the host should wait 4 seconds to repeat.

Here is another E2E thread that might provide a clue:

https://e2e.ti.com/support/power-management/f/196/t/556803

Regards,

Matt

0 Anton Kalinichenko over 5 years ago in reply to Matt Sunna

Prodigy 20 points

Hi Matt,

1. I tried to use various delays between HostFETControl() calls but this function is still unstable.

2. "sending one byte of data to change the state of the FETs" does not work at all on my side.

So I implemented a workaround to poll CHG pin with 4 sec delay after every charge command. If CHG pin does not correspond to the required state - command is reissued.

Best regards,

Anton

0 Matt Sunna over 5 years ago in reply to Anton Kalinichenko

TI__Guru* 81035 points

Hi Anton,

I'm glad to hear you found a solution. Thanks for sharing this update.

Matt

Power management

Power management forum

BQ78350-R1: BQ78350-R1 - 0x2B HostFETControl command failure