466130 Datasheet, PDF (26/36 Pages) ATMEL Corporation – 8-bit Microcontroller with 64/128K Bytes of ISP Flash

7. Errata
8. AT90USB1287/6 Errata.
8.1 AT90USB1287/6 Errata History
Silicon
Release
First Release
Second Release
Third Release
90USB1286-16MU
90USB1287-16AU
Date Code up to 0648
Date Code up to 0714
and lots 0735 6H2726*
Date Code from 0709 to 0801
except lots 0801 7H5103*
from Date Code 0722 to 0806
except lots 0735 6H2726*
Lots 0801 7H5103* and
Date Code from 0814
Date Code from 0814
Note ‘*’ means a blank or any alphanumeric string
90USB1287-16MU
Date Code up to 0701
Date Code from 0714 to 0810
except lots 0748 7H5103*
Lots 0748 7H5103* and
Date Code from 0814
8.2 AT90USB1287/6 First Release
• Incorrect CPU behavior for VBUSTI and IDTI interrupts routines
• USB Eye Diagram violation in low-speed mode
• Transient perturbation in USB suspend mode generates over consumption
• VBUS Session valid threshold voltage
• USB signal rate
• VBUS residual level
• Spike on TWI pins when TWI is enabled
• High current consumption in sleep mode
• Async timer interrupt wake up from sleep generate multiple interrupts
9. Incorrect CPU behavior for VBUSTI and IDTI interrupts routines
The CPU core may incorrectly execute the interrupt vector related to the VBUSTI and IDTI
interrupt flags.
Problem fix/workaround
Do not enable these interrupts, firmware must process these USB events by polling VBUSTI
and IDTI flags.
8. USB Eye Diagram violation in low-speed mode
The low to high transition of D- violates the USB eye diagram specification when transmitting
with low-speed signaling.
Problem fix/workaround
None.
7. Transient perturbation in USB suspend mode generates overconsumption
In device mode and when the USB is suspended, transient perturbation received on the
USB lines generates a wake up state. However the idle state following the perturbation does
26 ATmega32U6/AT90USB64/128
7593JS–AVR–03/09