This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

BQ24090: normal temperature fault indication

Part Number: BQ24090

HI Sir/Mdm,

I had been using his BQ24090, and during out testing of this charger, we found the out of normal temperature fault indication from this IC. Usual understand is temperature fault, charging stop and charge light will go OFF. However, this IC has it that temperature fault, charge light remains ON though charging has stop. In the datasheet (pg19), it says “ON for 1st charge” on temperature fault.

My question are, what is the reason behind this indication mode to allow the charge light to remain ON while charging has stopped. This created a false impression that charging is still in progress.

The phrase “1st charge” has been used a number of times, what is the reason that 1st charge cycle is made different from subsequent cycles?

Regard's

Jason Teoh

  • Hello
    /CHG is a very basic indication that charge is in progress, the user has plugged the device into USB port and only wants to know when the charge is complete.
    The /CHG pin will go low for the first charge only. Also during this time if charging stops due to TS temperature fault the /CHG pin will remain low, indicating charge. The unit has features to work with an elevated temp, if die temp is high it will reduce current or stop charge. High temp on battery will stop charge until temp is reduced.
    After charge is complete the pin will go high impedance and will not indicate a recharge.