We are trying to decide between two different DACs in the same family that are pin compatible. One DAC is about 3x more expensive, but has higher resolution and will definitely work. The second is less expensive, but has lower resolution. We will have to do more extensive testing to verify that the lower resolution DAC works for our applications. We are a startup and would like to sell our product out as soon as possible. If we pass the FCC test with the higher resolution DAC, and switch to the lower resolution DAC later would we have to retest?
The rules I found on the FCC site said that if the part is electrically equivalent we would not necessarily need to re-test, but I am not sure if changing DAC resolution is considered "electrically equivalent".
Our device uses RFID, so it is an intentional radiator, but the DAC is not related to the RFID circuit.