Datasheet

ATmega48A/PA/88A/PA/168A/PA/328/P
 2018 Microchip Technology Inc. Data Sheet Complete DS40002061A-page 647
2. TWI Data setup time can be too short
When running the device as a TWI slave with a system clock above 2MHz, the data setup time for the first
bit after ACK may in some cases be too short. This may cause a false start or stop condition on the TWI
line.
Problem Fix/Workaround
Insert a delay between setting TWDR and TWCR.
40.4.4 Rev B to E
Not sampled.
40.4.5 Rev. A
•
Power consumption in power save modes
• Startuptimeforthedevice
1. Powerconsumptioninpowersavemodes
Power consumption in power save modes will be higher due to improper control of internal power
management.48
Problem Fix/Workaround
This problem will be corrected in Rev B.
2. Startup time for the device
Due to implementation of a different NVM structure, the startup sequence for the device will require longer
startup time.
Problem Fix/Workaround
Thereisnofixforthisproblem.
40.5 Errata ATmega168A
The revision letter in this section refers to the revision of the ATmega168A device.
40.5.1 Rev K
•
Full swing crystal oscillator not supported
• Parallel programming timing modified
• Write wait delay for NVM is increased
• Changed device ID
• Analog MUX can be turned off when setting ACME bit
• TWI Data setup time can be too short
1. Full swing crystal oscillator not supported
The full swing crystal oscillator functionality is not available in revision K.
Problem fix/workaround
Use alternative clock sources available in the device.