Question about the PIC18F452 chip?

Question

I try to order a PIC18F452 micro controller chip, but when i look at the site, i saw PIC18F452-E/L, PIC18F452-E/ML, PIC18F452-E/P, PIC18F452-I/PT, PIC18F452-I/P, PIC18F452-I/ML

What are the difference between them?
what is those letter behind the model # mean? such as E/L, E/ML, etc

Answer 1

The letter before the / gives the temperature specification.
none = 0 to 70 C
E = -40 to +125 C (E means extended)
I = -40 to +85 C (I means industrial)

The letters after the / give the package type.
L = Plastic leaded chip carrier (PLCC)
ML = Quad flat pack, no lead (QFP)
P = Plastic DIP
PT = Plastic thin quad flat pack (TQFP)

If you are a hobbyist, then the temperature rating does not matter much to you.

But, be very careful with the package type. That DOES matter. If you get the wrong package, then the chip will not fit on the PC board that you want to put it in. Find out what kind your board requires. If you are planning to make your own PC board, then you probably want to get the plastic DIP. It's much easier to hand solder. The other packages can't be soldered without special tools.