BQ24253: BQ24253 doesnt enter into battery charging mode

HI Yagnik,

Is LDO ~=5V?  Is STAT blinking to indicate a fault?  Pin 8 is /PG not INT.  Does indicate power good?  Does SW have a squarish waveform to indicate that the converter is switching?

Note that the input current limit is set by D+/D- and if connected to a legacy USB port, could be set to 100mA.  The ENx lines have to be toggled after D+/D- completes (/PG goes low) to change the input current limit to the ILIM pin setting, which is the max with ILIM=GND.

Regards,

Jeff

Hi Jeff,

Apologies for the late response.

Thank you very much for your support.

The issue is related to the charge enable pin. I have added strong PD and now it is working for a few cases.

There is one more issue that I mentioned below. We use 1 Amp for the power path and 1 Amp for the battery charging.

For example

// For the below example battery must be discharged which is as expected

                                                    _________________To board power

                                                   |

                                                   |    

USB power is not present--->>Battery charger BQ24253--->>FuelGauge-->>Battery

// For the below example battery must be charged and it is charged which is as expected

                                                    _________________To board power(board is in sleep mode so no current drown)

                                                   |

                                                   |    

USB power is present--->>Battery charger BQ24253--->>FuelGauge-->>Battery

// For the below example battery is not charging instead of that it discharged which is the issue. Can we resolve this issue?

                                                    _________________To board power taking 600-700 mA current

                                                   |

                                                   |    

USB power is present--->>Battery charger BQ24253--->>FuelGauge-->>Battery

We have a 3 Amp charger.

The charger on shortcircuits mode is able to give 3.2Amp current so the charger looks good. Since all of our other products have the same charger.

We haven't connected the D+/D- pins right now.

You mean to say short D+ with D- line right? Not D+ with connector and D- with connector. Since from the USB cable we only have power pins. D+ and D- lines are open from the connector to the power adapter cable.

Hi Yagnik,

I recommend connecting the D+ and D- pins on the IC and not connecting those pins to the adapter.

Regards,

Jeff

Ok i have mounted those resistors as per your suggestion. Please the connection of USB with bat charger

Still issue is same.

Hi Yagnik,

Is STAT pin high or low or blinking?  What is the voltage at VIN pin?  If there a square like waveform on SW pin similar to the datasheet curve below?

If you toggle one of the ENx, does the charger start charging?

Regards,

Jeff

STAT is not blinking.

VIN = 5V

Yes, when the board in not drawing the current then we got the waveform.

When the board starts taking a current of around 500 mA then the waveform is not coming. So I think the ENx pin is not the issue. Still will try.

When I used the bc2.1  compliant charger then at it is going to be charging. That means this IC is not going to check the EN1/EN2 pin logic when we not use D+/D- detection logic. instead of that, it will limit the current of 500 mA. which is nonstandard adapter detection.

However when D+/D+ is detected then it limits around 1500 mAmp as per table 3 in datasheet.

But for non-USB compliant chargers EN1 = 1, EN2 = 0 it limits very less current may be 500 mA or something. Or might be it is not going to detect the EN1/EN2 pin instead of that it uses the nonstandard charger as per table no 3 last raw.

Well charger is going to charge the battery when the board is in sleep mode as I mentioned earlier(Shown in 3 use cases earlier)

Out of that from the below use case, it is going to be charged. 

// For the below example battery must be charged and it is charged which is as expected

                                                    _________________To board power(board is in sleep mode so no current drown)

                                                   |

                                                   |    

USB power is present--->>Battery charger BQ24253--->>FuelGauge-->>Battery

// For the below example battery is not charging instead of that it discharged which is the issue. Can we resolve this issue?

                                                    _________________To board power taking 600-700 mA current

                                                   |

                                                   |    

USB power is present--->>Battery charger BQ24253--->>FuelGauge-->>Battery