User manual

Atmel-ICE [USER GUIDE]
42330A-MCU-07/2014
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5.4 Architecture Description
The Atmel-ICE architecture is shown in the block diagram in Figure 5-1, “Atmel-ICE block
diagram” on page 26.
Figure 5-1. Atmel-ICE block diagram
5.4.1 Atmel-ICE Mainboard
Power is supplied to the Atmel-ICE from the USB bus, regulated to 3.3V by a step-down switchmode regulator.
The VTG pin is used as a reference input only, and a separate power supply feeds the variable-voltage side of
the on-board level converters At the heart of the Atmel-ICE mainboard is the Atmel AVR UC3 microcontroller
AT32UC3A4256, which runs at between 1MHz and 60MHz depending on the tasks being processed. The
microcontroller includes an on-chip USB 2.0 high-speed module, allowing high data throughput to and from the
debugger.
Communication between the Atmel-ICE and the target device is done through a bank of level converters that
shift signals between the target's operating voltage and the internal voltage level on the Atmel-ICE. Also in
the signal path are zener overvoltage protection diodes, series termination resistors, inductive filters and ESD
protection diodes. All signal channels can be operated in the range 1.62V to 5.5V, although the Atmel-ICE
hardware can not drive out a higher voltage than 5.0V. Maximum operating frequency varies according to the
target interface in use.