Datasheet

31
ATmega48A/PA/88A/PA/168A/PA/328/P [DATASHEET]
Atmel-8271HS-AVR- ATmega-Datasheet Summary_08/2014
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.
11.4.2 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.
11.5 Errata ATmega168A
The revision letter in this section refers to the revision of the ATmega168A device.
11.5.1 Rev. E
•
Analog MUX can be turned off when setting ACME bit
• TWI Data setup time can be too short
1. Analog MUX can be turned off when setting ACME bit
If the ACME (Analog Comparator Multiplexer Enabled) bit in ADCSRB is set while MUX3 in ADMUX is '1'
(ADMUX[3:0]=1xxx), all MUXes are turned off until the ACME bit is cleared.
Problem Fix/Workaround
Clear the MUX3 bit before setting the ACME bit.
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.
11.6 Errata ATmega168PA
The revision letter in this section refers to the revision of the ATmega168PA device.