When searching for ON Semiconductor components, you may run across the same device marked with one of two different suffixes - 1G, as per MBR140ESFT1G , or 3G as per MBR140ESFT3G. What do these suffixes call out? Are these parts interchangeable?
The IC is exactly the same in both these cases, and are 100% interchangeable on your board. ‘1G’ and ‘3G’ are packaging suffixes, with 1G calling out a 3k-piece 7" reel and 3G calling out a 10k-piece 13" reel. Once off the reel, there’s no difference at all between the products.