BQ24610: Stat1 and Stat2 lights are both on

Hello,

This is an invalid condition. Can you please send your schematic?

Regards,

Mike Emanuel

SCHEMATIC

It "may" be due to a reverse polarity condition on our charger input, but I have not validated that, it is just a theory from the engineer who broke this board.  He also recently broke another which now has the same symptoms.  

We have a few reworks that aren't shown on this schematic, namely we have jumpered across Q3 and Q5 to make one return path.  I will grab a few critical test point measurements on a good and bad board and post them.

I await your results and schematics. 

Regards,

Mike Emanuel

The schematic is in the post above.  Unfortunately, my board got a "thermal event" while working on it yesterday while I was working on it.  I think I accidentally shorted pins 19 and 20 while probing and it burned up Q8 and Q9.  I have another board exhibiting the same behavior and will try again, more carefully, on Tuesday. 

Thanks,

Ben

Keep me posted!

Can you please share the schematic as a normal download? I am having trouble viewing it.

Sorry for the delay, I took a vacation :)  I'm not sure how to attach the schematic any other way.  If you download the PDF locally, then open it, your native PDF viewer will work better.  I'm not sure why the online viewer makes it so blurry.   Is there another way of uploading a file that I can't figure out?  In the insert tab below it just allows me to put in a picture.  Here is another link to the schematic in a zip file, that might be easier. drive.google.com/.../view

I see your issue now, you must request access for the file.  Let me see if I can host the files elsewhere. 

Try this one:  drive.google.com/.../view

I took measurements of all the pins we are using in our schematic at the battery charger, I've attached a spreadsheet.  I've measured a good board and bad board with and without the charger connected.  https://docs.google.com/spreadsheets/d/10LzxbBQfMt0a7lrvTt3cdjs37NUdYzYC/edit?usp=sharing&ouid=111065868614272902578&rtpof=true&sd=true

Ben,

We do not use google docs for my group. Here are the instructions:

1. Click "Insert"

2. Click "Image/video/file"

3. Click "Upload"

4. Click "Ok"

0407.bq24610.pdf

I have uploaded the datasheet as an example.

Regards,

Mike Emanuel

Stat1 &Stat2 LED's on data (1).xlsx

DaisyIoUpCorePlus.pdf

the issue with the second column, "bad bd/no charge pwr", is that the LED's indicate the invalid state, with stat1 and stat2 lights both on, so there is something wrong with that column more than just it being in sleep mode.

The setup for "bad bd/ with charge" is a board in the invalid state, with stat1 and stat2 on, as well as 24V applied to the charge input.

Mike,

What is the indication state if the device goes into undercurrent protection mode described in 10.2.1.2.1. Can I test this any way besides just wiring up the sense resistor and looking for the voltage drop?

I'm looking into this because we have a BOM error on our build, where we placed a .005 ohm sensor resistor instead of a .01 ohm sense resistor.  

Thanks,

Ben

"The BQ2461x has cycle-by-cycle charge undercurrent protection (UCP) by monitoring the charging-current sensing resistor to prevent negative inductor current. The typical UCP threshold is 5-mV falling edge corresponding to 0.5-A falling edge for a 10-mΩ charging-current sensing resistor."