what different about PIC16F877-04/P and PIC16F877-I/P

Somkiat · Guest

any one can tali me? please

Haplo · Joined: 06 Sep 2003 Posts: 659 Location: Sydney, Australia

The '-04' shows the maximum clock speed of the processor is 4Mhz, while '-I' means industrial temperature range (-40°C to +85°C). For more information refer to page 211 of the datasheet (PIC16F87X PRODUCT IDENTIFICATION SYSTEM).

Somkiat · Guest

Thank you Haplo
So,PIC16F877-I/P has MAXIMUM 4 MHz right?

Haplo · Joined: 06 Sep 2003 Posts: 659 Location: Sydney, Australia

I'm not sure about this. I know the chips like PIC16F870 which come in the PIC16F870-I/xx format are 20MHz. But according to the PIC16F877 datasheet, the PIC frequency range is always stated before the 'I' suffix, so forexample it should be PIC16F877-20I/P.
Are you sure you have a PIC16F877-I/P? It is probably a 20MHz part.

Somkiat · Guest

Hi Haplo
I 'am sure I have PIC16F877-I/P from vendor in Thailand ,But vendor not clear about this problem.
I test PIC16F877-I/P with crystal 20MHz it work fine,But I not sure when for long run

sory for my english

Thank you again

valemike · Guest

I once asked an FAE how they are different. I was told that they come from the same batch, but that the 20MHz-rated parts are tested and guaranteed to run at 20MHz. So you can overclock a 4MHz-rated part, but it's not guaranteed.

Haplo · Joined: 06 Sep 2003 Posts: 659 Location: Sydney, Australia

According to the device datasheet all parts should come with frequency range in their ID. Yours doesn't. I think you should email Microchip tech support and ask them. Your chips may be a 20MHz part (that's probably the case), or a 4MHz part, or even a clone.