Hi!
We have been working on implementing the cell voltage, TOS and Pack PIN voltage calibration sequence that is described in "BQ769x2 Calibration and OTP Programming Guide". We are using a two point calibration sequence, and calculate on the difference between the measurement points. Cell voltages works good for us, but we have some problems with the two PINs.
Question 1:
The READ_CAL1 (0xf081) command have twelve byte response according to the manual, but the AFE returns 14 bytes on this command. What is the last bytes, and is it still correct that the TOS and PACK pin offset is in bytes 6 and 8 as states in the manual?
Question 2:
We are operating the AFE in userV of mV. What is the expected input in the formulas for offset and gain? For cell calibration this works fine, but when we apply the formula to the Pack and TOS PIN, our calculations get out of int16 range. (E.g we input 20V and 16V here, the difference will either be 4000mV or 400cV in the formula below)
Question 3:
The offset value for pack and tos pin is not included in the example code. Is that because it's not used? Documentation states that it can be calculated in the same way as for the cell voltages. Does that mean that the divisor shall be 2^16 in this formula:
Best regards
/Erik Almqvist