Datasheet

17
4317KS–AVR–03/2013
AT90PWM2/3/2B/3B
7. Errata
7.1 AT90PWM2&3 Rev. A (Mask Revision)
• PGM: PSCxRB Fuse
• PSC: Prescaler
• PSC: PAOCnA and PAOCnB Register Bits (Asynchronous output control)
• PSC: PEVxA/B Flag Bits
• PSC: Output Polarity in Centered Mode
• PSC: Output Activity
•VREF
•DALI
• DAC: Register Update
• DAC: Output spikes
• DAC driver: Output Voltage linearity
• ADC: Conversion accuracy
• Analog comparator: Offset value
• Analog comparator: Output signal
• PSC: Autolock modes
• DALI: 17th bit detection
• PSC: One ramp mode with PSC input mode 8
1. PGM: PSCnRB Fuse
The use of PSCnRB fuse can make the parallel ISP fail.
Workaround:
When PSCnRB fuses are used, use the serial programming mode to load a new program
version.
2. PSC: Prescaler
The use of PSC's prescaler have the following effects :
It blocks the sample of PSC inputs until the two first cycles following the set of PSC run bit.
A fault is not properly transferred to other (slave) PSC.
Workaround:
Clear the prescaler PPREx bit when stopping the PSC (prun = 0), and set them to appropri-
ate value when starting the PSC (prun = 1), these bits are in the same PCTL register
Do not use the prescaler when a fault on one PSC should affect other PSC’s
3. PSC: PAOCnA and PAOCnB Register Bits (Asynchronous output control)
These register bits are malfunctioning.
Workaround:
Do not use this feature.
4. PSC: PEVnA/B flag bits
These flags are set when a fault arises, but can also be set again during the fault itself.
Workaround:
Don't clear these flags before the fault disappears.