AT90USB647-AU Atmel, AT90USB647-AU Datasheet - Page 29

• Manufacturer Part Number: AT90USB647-AU
• Description: MCU, 8BIT, AVR, 64K FLASH, USB, 64TQFP
• Manufacturer: Atmel

Specifications of AT90USB647-AU

• No. Of I/o's: 48
• Eeprom Memory Size: 2KB
• Ram Memory Size: 4KB
• Cpu Speed: 20MHz
• No. Of Timers: 4
• No. Of Pwm: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 64KB
• Oscillator Type: External, Internal
• Controller Family/series: AVR USB
• Rohs Compliant: Yes
• Lead Free Status / Rohs Status: Details

7593KS–AVR–11/09
2. High current consumption in sleep mode
1. Asynchronous timer interrupt wake up from sleep generates multiple interrupts
Problem Fix/workaround
No known workaround, enable AT90USB64/128 TWI first versus the others nodes of the
TWI network.
If a pending interrupt cannot wake the part up from the selected mode, the current consump-
tion will increase during sleep when executing the SLEEP instruction directly after a SEI
instruction.
Problem Fix/workaround
Before entering sleep, interrupts not used to wake up the part from the sleep mode should
be disabled.
If the CPU core is in sleep and wakes-up from an asynchronous timer interrupt and then go
back in sleep again it may wake up multiple times.
Problem Fix/workaround
A s o f t w a r e w o r k a r o u n d i s t o w a i t w i t h p e r f o r m i n g t h e s l e e p i n s t r u c t i o n u n t i l
TCNT2>OCR2+1.
AT90USB64/128
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