battery life estimate

[Ridhi]

i have nrf52832 using nrf sdk version_17 and s132.

I have application for logging

i have followed steps:

1). intially device in sleep mode

current: 0.35 micro Amp

2). press button for 5 sec and then device advertises for 30 secs: 

current: 84.29 micro Amp

3). connect on nrf connect app for mobile

displays services and characteristics 

current: 740.40 micro Amp

4). chip erase 5 secs: 14.81 mA

5). takes about 100 logs in interval of 2 secs

each log: 7.03mA 

amidst logs: 2.11 micro Amp

so total 100 logs almost take 3min 22 secs and current: 1.57mA

6). disconnect and then advertise and connect and notify enable to get data: 

data log getting current: 741.20 micro Amp for 52 seconds

I am using coin cell battery CR2450 LITHIUM 3V

attaching power profiler trace.

pls help to calculate the life of device

[Ridhi]

Hello karl,

i hav shared you the power profiler trace and battery is CR2450 

1). at first my device is in unconnected mode for 15 secs giving average current 0.35 micro amp for window selected

2). then i press button for 5 secs it gives about 6.48mA 

3). the device then goes into advertsisng state. giving current  84.29 micro Amp

max the device can advertise for 3 mins

4). then with 1000ms connection interval set the sevice and charactersitics are displayed for say about 30 seconds 

5). then we take about 100 logs after 2secs interval :1 log takes 6.38mA current

6). then press button for 5 secs and then get the data after connection mode using notification

Maximum i can set to get 16000 logs and the durstion between logs can be set max to 10 mins.

Snips.rar

[Karl Ylvisaker]

Ridhima, please read my previous reply thoroughly.
You have shared this same information with me multiple times - I have acknowledged this - but it is impossible to make an estimate on battery life expectancy without any notion of how frequent the scenario you describe will occur.

I have provided you with all you need to conduct these calculations yourself, I recommend that you do so instead of providing me the scenario details yet again.

Best regards,
Karl

[Ridhi]

Basically i have a temperature humidity SHT40 sensor, winbond nor 2MB flash and nrf52832 ble dev kit. I am taking about 100 readings from SHT40 sensor ie 12bytes  after 2 seconds interval. Then storing it in flash and able to read over nrf connect using notification enable.

Karl i am finding difficulty in battery estimation actually I have shared you with details about 1 complete scenario how all steps are followed by the user.

[Karl Ylvisaker]

Thank you for elaborating, but you are still not answering my questions.
How often does it happen? How often will the button be pressed and the readings performed?
This is paramount to perform any sort of estimate of the battery life. Will it happen once every day, once every hour, or once every minute?
How long will each typical connection last?

Please read my previous replies again. Try to make a calculation following the method I outlined on your own, and show them to me. Calculate the average current draw for a complete scenario, along with the current draw during sleep. Calculate how much of the time the device will spend in the current draw scenario, and how much of the time it will be sleeping. Then, make an average for the overall current draw and calculate how many hours your battery will last under this load.

Best regards,
Karl