Hello! My name is Doyoung . I'm working on embedded sensor network, now.
I have some questions about your battery monitoring method.
First of all, ADC_Count(Data from adc converter) = Vin(Vbatt) * ADC_FS /V ref
so, Vbatt= ADC_Count * Vref / ADC_FS.
But as you know,the manual says that Vbatt = (Vref*ADC_FS/ADC_Count).
I think that is wrong. And about V ref=1.223V.
The schematic of Mica2 shows that AREF pin cennects to VDD(3.3V) and
The Voltage drop of LM4041(voltage reference IC) goes to ADC7.
It dosesn't make sense that LM4041 was connected to ADC7 pin. Not AREF pin.
Following above schematics description,
Vref(Reference voltage of ADC converter) = 3.3V
Vin( ADC7 pin)=1.223V
Am I wrong or you made some mistakes ?
I think the right method of battery monitoring is checking battery voltage
directly. Not port's voltage.
Is there any points I missed?
Please Let me know If I did. Thanks in advance.
with my best regard
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