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Calculate battery life
Use this as generic calculator to calculate battery life and capacity:
C = Battery capacity (mAh)
BL= Battery life (years)
Is = Current when device is in sleep mode (mA)
Itx = Current when device is in transmit mode (mA)
Irx = Current when device is in Receive mode (mA)
Imeas = Current when device is in measurement mode (mA) [it depends on technology used and application]
Ttx = Amount of time that device is in Transmit (TX) mode (ms)
Trx = Amount of time that device is in Receive (RX) mode (ms)
Tmeas = Amount of time that device is in measurement mode (ms) [depends on technology used and application]
Ta = Amount of time that device is active (ms)
Ta = Ttx+ Trx +Tmeas
U = Usable capacity after taking into account self-discharge (%)
N = Number of times the device will be active per day
cU = Capacity after taking into account discharge rate (mAh) = C*(U/100)
T = Milliseconds per hour = 3600000
cA = Active capacity usage per day = N*(Ttx*Itx + Trx*Irx + Tmeas*Imeas)/T
cS = Sleep capacity usage per day = Is*( 24-((Ttx + Trx + Tmeas)*N/T) )
cT = Total capacity consumed per day = cA+cS
Battery Life (days) = (cU/cT)/24
Battery Life (years) = days/365.24