I use the ADMP441 and I want to know how to compute the SPL value for a given digital output word. I know, that 120 dB SPL is mapped to the FS value of the ADC. Is the EIN value also mapped to the the value of the noise floor so that 33 dB SPL (EIN) is equivalent to the -87 dBFS word? Is the relationship between the SPL and the ADC word linear in this range? The data sheet and the application notes I read, couldn't answer this questions.
Thank you very much for any kind of help