ATTINY45 datasheet(21/30 Pages) ATMEL

21 / 30 page

2586L–AVR–06/10

ATtiny25/45/85

more than 3V. Similarly, if supply voltage can not be raised above 2V then operating fre-

quency should be more than 2 MHz.

This feature is known to be temperature dependent but it has not been characterised.

Guidelines are given for room temperature, only.

4. Timer Counter 1 PWM output generation on OC1B – XOC1B does not work correctly

Timer Counter1 PWM output OC1B-XOC1B does not work correctly. Only in the case when

the control bits, COM1B1 and COM1B0 are in the same mode as COM1A1 and COM1A0,

respectively, the OC1B-XOC1B output works correctly.

Problem Fix/Work around

The only workaround is to use same control setting on COM1A[1:0] and COM1B[1:0] control

bits, see table 14-4 in the data sheet. The problem has been fixed for Tiny45 rev D.

8.2.4

Rev A

• Too high power down power consumption

• DebugWIRE looses communication when single stepping into interrupts

• PLL not locking

• EEPROM read from application code does not work in Lock Bit Mode 3

• EEPROM read may fail at low supply voltage / low clock frequency

1. Too high power down power consumption

Three situations will lead to a too high power down power consumption. These are:

– An external clock is selected by fuses, but the I/O PORT is still enabled as an output.

– 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

ATTINY45 Datasheet(PDF) 21 Page - ATMEL Corporation