This application note summarizes the differences between ATmega48, ATmega88 and ATmega168. Refer to the datasheets for detailed information on the devices.
The document serves as a guide for migrating applications between the ATmega48, ATmega88, and ATmega168 microcontrollers. It highlights that while these devices are pin and functionality compatible, differences in memory sizes require minor modifications.
Key areas of comparison include Flash, EEPROM, and SRAM capacities; interrupt vector configurations where ATmega168 uses two instruction words per vector compared to one for the others; boot loader support availability which is absent in the ATmega48; and variations in flash page sizes, lock bits, device signatures, and fuse settings.
The main difference is the difference in memory sizes.
No, the ATmega48 does not have Read-While-Write support or a separate Boot Loader Section.
Each Interrupt Vector occupies two instruction words in ATmega168, but only one instruction word in ATmega48 and ATmega88.