SST25VF064C Serial Flash from Microchip

[MChapman]

I have a question that is primarily a curiosity. The SST25VF064C chip comes in 3 packages. I will be hand placing the board so, for ease and accuracy, will focus on the two SOIC packages. My question is a result of this device coming in a 8 pin and 16 pin SOIC. Half the pins in the 16 pin SOIC are NC.

In what application would having this 16 pin package be of more benefit over the 8 pin package?
http://http://www.microchip.com/wwwproducts/Devices.aspx?dDocName=en549422

 

[(*steve*)]

I was initially thinking that perhaps it provides better heatsinking, but in this application I doubt that would be significant.

Another option is that it may replace a chip which uses these pins for special programming voltages etc. that this design no longer needs. Providing it in this package might make it simpler to use in existing designs.

Other than that, I don't know. Have you read the datasheet? It might have the explanation (I didn't see one in a quick scan).

It's even a possibility that it's a relatively old design and the initial versions required a die larger than would fit inside some of these smaller devices.

 

[MChapman]

I believe the second reason is correct. I've looked through other flash chips from various companies and noticed the same package options with the center 8 pins as NC.