at90pwm81-16se ATMEL Corporation, at90pwm81-16se Datasheet - Page 309

• Manufacturer Part Number: at90pwm81-16se
• Description: 8-bit Avr Microcontroller With 8k Bytes In- System Programmable Flash
• Manufacturer: ATMEL Corporation

29.4
7734M–AVR–03/10
Errata AT90PWM81 revD
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7. ADC measurement reports abnormal values with PSC2-synchronized
8. Over-consumption in power down sleep mode.
1. Clock Switch enable & disable
2. Crystal oscillator control with Clock Switch
3. BOD disable fuse
When using ADC in synchronized mode, an unexpected extra Single ended conversion can
spuriously re-start.This can occur when the End of conversion and the Trigger event occur
at the same time.
Work around:
No workaround
In Power-down mode, an extra power consumption up to 500µA may occur.
Work around:
No workaround
Clock Switch disable
Crystal oscillator control with Clock Switch
BOD disable fuse
Flash and EEPROM programming failure if CPU clock is switched
ADC Amplifier measurement is unstable
ADC measurement reports abnormal values with PSC2-synchronized conversions
Over-consumption in power down sleep mode
After a “Enable Clock Source” or a “Disable Clock Source” command, the command is still
active until the next access of CLKCSR register. If CLKSEL is written with a new value, the
corresponding clock will be unintentionnaly enabled or disabled.
Work around:
Atter the Enable or Disable command, write CLKCSR with value 1<<CLKCCE
When a Xtal oscillator is active and CLKSELR is written with a new value for the selection of
another clock source (for instance RC or WD) , the Xtal oscillator gain is not correct.
Work around:
After the commands “Enable Clock Source” and “Clock Source Switching”, write back CLK-
SELR with the values corresponding to the active Xtal oscillator
It is strongly advised to keep the BOD active. Indeed, the RC oscillator may lock if it is acti-
vated when the power suppy goes at a low voltage.
Work around:
If it is mandatory to disable the BOD, do not set the RC oscillator as clock source during
reset and makes sure the RC oscillator is never active when the power supply is below the
lowest POR voltage (2.6V).
conversions
AT90PWM81
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