AnsweredAssumed Answered

Discrepancy between AN4519 and MPL3115A Datasheet?

Question asked by overdamped on Dec 29, 2014
Latest reply on Jan 8, 2015 by Tomas Vaverka

I'm having trouble deciding how I should convert the value stored in the fractional part (bits 4-5) of the OUT_P_LSB for CTRL_REG_1 & ALT == 0 (a.k.a. the output pressure should be in pascals). The datasheet states that the value of the OUT_P is in unsigned Q18.2 format which should mean that bit 5 of the OUT_P_LSB would represent 2^-1 (a.k.a. 0.5) place while bit 4 of OUT_P_LSB would represent the 2^-2 place (a.k.a. 0.25)? However, it seems that Table 3 in AN4519 shows the exact opposite.

 

Is this a problem with the table, or am I completely wrong in my understanding of Q number formats?

Outcomes