The PGA308 is part of a family of sensor signal conditioning devices that is a sub-set of the PGA309. The PGA309 corrects for offset, gain, drift, and linearity errors, while the PGA308 only corrects for offset and gain errors. Customers who are not concerned about drift and linearity errors will use the PGA308. High end sensor customers who want to correct for linearity and temperature drift will use the PGA309.