Is "No battery plugged" detection possible? (MP2723A)

Hi,
I’m integrating the MP2723A into one of our products and I noticed an odd behaviour.
I’m working on the integration using the evaluation kit (EV2723A-QC-00A)

When using it without any battery (VBATT) connected, the charging state seems to go a little bit crazy because it constantly flip-flops from charging to fully charged.

Is there any way I can detect there’s no physical battery connected to ignore these strange state changes (or maybe even stop checking the charging state)?

All I could think of is checking the ICHG ADC value. When that’s 0 and the state is charging
, I assume there’s no battery. It kinda works, but I’m not very comfortable with this method.

Thanks in advance

Toni

Hi toni.barrera,

I’m looking into your question and will post an update soon.

Hi Toni,

In a real application, when there is no battery inserted, the NTC will also be invalid.
In this case, we can read the status as: NTC float. This also means “no battery” state.
And in this condition, VBATT is 0 and VSYS is regulated to constant VSYSMIN.
You can remove RT2 in the EVB to see such state.

Hi Bryan,
I think I’m missing something in your explanation.
Currently, I have EVB without a battery and I’m powering via USB.
The ADC values I’m getting are:
VBATT: 3940mV
VSYS : 4040mV
NTC : 49%
VIN : 5100mV
ICHG : 0mA
IIN : 79mA

When checking REG0Ch I’m getting 10110001
NTC float value is 0, so apparently the module is not detecting “NTC float” state

In addition, you say that VBATT should be 0 is this “NTC float” state, but clearly that’s not the case

Am I interpreting something incorrectly?

BR

Edit: Just for the record I have not yet removed RT2 because I’m not sure what will happen to the EVB general behavior when that’s not present.

Toni