Here is how to move the CutIn and CutOut voltages to something more useful for a battery monitor. The addition of two voltage dividers: R1/R2 and R3/R4 lets us move the CutIn and CutOut to 11.8V and 13.8V, respectively.
First, calculate R2 such that the Trig pin drops below 3.0V as the battery discharges below 11.8V. Using the familiar voltage divider equation (ratio and proportion) Vtrig/Vin = R2/(R1+R2).
Solving for R2: (Vtrig/Vin)*(R1+R2) = R2
Simplify: R2 = R1*(Vtrig/Vin) + R2*(Vtrig/Vin)
Gather terms: R2 - R2*(Vtrig/Vin) = R1*(Vtrig/Vin)
Simplify: R2 = R1*(Vtrig/Vin)/(1-Vtrig/Vin))
R2=499000*(3/11.8)/(1-3/11.8)) = 499000*(3/11.8)/(1-3/11.8)) = 170K
Second, calculate R4 such that the Thrs pin rises above 6.0V as the battery charges above 13.8V.
R2=499000*(6/13.8)/(1-6/13.8)) = 499000*(6/13.8)/(1-6/13.8)) = 384K
Remaining to do:
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