BQ35100: BQ35100

Part Number: BQ35100 Hi, There is a customed board with BQ35100 and MCU. I setup BQ35100 in EOS mode (reg. 0x41b1), and modified R Data Seconds (reg. 0x4255) setup 1 second. To get data (voltage, current, temperature) the following sequence is used: 1. Enable BQ; 2. Start BQ (send start command); 3. Read data(voltage or current or temperature); 4. Stop BQ (send stop command); 5. wait for timeout specified in R Data Seconds (expected 1 s) wait until G_DONE bit is set; 6. Disable BQ; The problem is that actually it takes about 4 min (instead of expected 1 s) to wait G_DONE is set. Do I need to send some other command to activate the setting? thanks

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Lurii, I have not seen this and programmed a value of 1 myself to test. Are you sure the gauge is receiving the [Gauge Stop] command? The [GA] bit should clear if so. I also don't recommend a value of 1 second. the gauge needs time to fill in the voltage sampling buffer to accurately calculate the measuredZ. Thanks, Eric Vos

Thanks for reply. Regarding "the gauge is receiving Stop command" i'm not sure, i need to verify this with logic analyzer. 1. As far as, I get it the GA bit should be cleared after Stop command is received properly (correct me if I'm wrong). So, should I check GA bit instead of G_DONE in the Control_Status? What is the purpose of G_DONE bit? 2. What is the minimum value of R data seconds reg. to get accurate value of voltage, current and temperature? This is quite weird behavior, because at the first i used the default value of R Data Seconds (15 sec) and the following sequence: - enable BQ; - start BQ (send command and wait until bit GA is set); - stop BQ (send command and wait until bit G_DONE is set); - read data form BQ; - disable BQ; In this case it takes around 15 sec. to read data from BQ (as expected according to datasheet). Then I tried to reduce R Data Seconds to less value (1 sec, 5 sec, 10 sec), but instead of reducing response time it takes unexpected ~4 min to read data (to wait until G_DONE is set). Perhaps the right sequence should be the following: - enable BQ; - start BQ (send command and wait until bit GA is set); - stop BQ (send command and wait until bit GA is clear); - read data (); - disable BQ; Please, provide me a feedback. Thanks.

1) yes sending Gauge_Stop should set GA =0 if it was received properly by the gauge. 2) The minimum we recommend is 15Sec which is why it is our default. If it needs to be lower testing should be done on your side to make sure results are consistent. Both procedures should work, but since measuredZ and SOH are updated after GDone. I would follow - enable BQ; - start BQ (send command and wait until bit GA is set); - stop BQ (send command and verify bit GA is clear); -Wait until GDONE = 1 - read data (); - disable BQ;

hi, followed the recommendation of Eric Vos24 and figured out that after sending STOP command the [GA] bit is still set and furthermore waiting for bit [G_DONE] to be set never happens (it is 0 for a very long time). It seems that there is a problem with STOP command. I tried to set R Data Seconds reg. to different values (1 sec, 5 sec, 15 sec), but the result is the same (wait bit [G_DONE] set for a very long time). What might be the problem with STOP command (other command seems to work properly)?

Hello Iurii, Can you wait for a while longer prior to sending STOP? Say 2 more seconds?

Hi, yes I tried this, but result is the same (bit GA is still set after STOP command has been sent). After START has been sent MCU waits for [GA] bit is set (first line on the Logic analyzer log: 0x81) then MCU wait for 2000 ms and sends STOP command (0x12 line 5), then MCU check [GA] bit, but it is still 1 (last but one line 0x81)

Hi, yes I tried this, but result is the same (bit GA is still set after STOP command has been sent). After START has been sent MCU waits for [GA] bit is set (first line on the Logic analyzer log: 0x81) then MCU wait for 2000 ms and sends STOP command (0x12 line 5), then MCU check [GA] bit, but it is still 1 (last but one line 0x81)

Hi, yes I tried this, but result is the same (bit GA is still set after STOP command has been sent). After START has been sent MCU waits for [GA] bit is set (first line on the Logic analyzer log: 0x81) then MCU wait for 2000 ms and sends STOP command (0x12 line 5), then MCU check [GA] bit, but it is still 1 (last but one line 0x81)

It most likely might be that your voltage is not stable yet. Can you provide us a bqStudio log file?