2

7766DS–AVR–01/09

ATmega16U4/ATmega32U4

– Byte Oriented 2-wire Serial Interface

– Programmable Watchdog Timer with Separate On-chip Oscillator

– On-chip Analog Comparator

– Interrupt and Wake-up on Pin Change (8xPCINT + 5xINT sources)

– On-chip Temperature Sensor (see A/D Converter section)

– Power-on Reset and Programmable Brown-out Detection

– Internal 8 MHz Calibrated Oscillator

– Internal clock prescaler & On-the-fly Clock Switching (Int RC / Ext Osc)

– External and Internal Interrupt Sources

– Six Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, Standby, and Extended Standby

– All I/O combine CMOS outputs and LVTTL inputs

– 26 Programmable I/O Lines

– 44-lead TQFP Package, 10x10mm

– 44-lead QFN Package, 7x7mm

– 2.7 - 5.5V

– Industrial (-40°C to +85°C)

– 8 MHz at 2.7V - Industrial range

– 16 MHz at 4.5V - Industrial range

Note:

1. See “Data Retention” on page 8 for details.