Datasheet
219
2586N–AVR–04/11
ATtiny25/45/85
– The EEPROM is read before entering power down.
– VCC is 4.5 volts or higher.
Problem fix / Workaround
– When using external clock, avoid setting the clock pin as Output.
– Do not read the EEPROM if power down power consumption is important.
– Use VCC lower than 4.5 Volts.
2. DebugWIRE looses communication when single stepping into interrupts
When receiving an interrupt during single stepping, debugwire will loose
communication.
Problem fix / Workaround
– When singlestepping, disable interrupts.
– When debugging interrupts, use breakpoints within the interrupt routine, and run into
the interrupt.
3. PLL not locking
When at frequencies below 6.0 MHz, the PLL will not lock
Problem fix / Workaround
When using the PLL, run at 6.0 MHz or higher.
4. EEPROM read from application code does not work in Lock Bit Mode 3
When the Memory Lock Bits LB2 and LB1 are programmed to mode 3, EEPROM read does
not work from the application code.
Problem Fix/Work around
Do not set Lock Bit Protection Mode 3 when the application code needs to read from
EEPROM.
5. EEPROM read may fail at low supply voltage / low clock frequency
Trying to read EEPROM at low clock frequencies and/or low supply voltage may result in
invalid data.
Problem Fix/Workaround
Do not use the EEPROM when clock frequency is below 1MHz and supply voltage is below
2V. If operating frequency can not be raised above 1MHz then supply voltage should be
more than 2V. Similarly, if supply voltage can not be raised above 2V then operating fre-
quency should be more than 1MHz.
This feature is known to be temperature dependent but it has not been characterised.
Guidelines are given for room temperature, only.