3
32142DS–06/2013
ATUC64/128/256L3/4U
1. Description
The Atmel
®
AVR
®
ATUC64/128/256L3/4U is a complete system-on-chip microcontroller based
on the AVR32 UC RISC processor running at frequencies up to 50MHz. AVR32 UC is a high-
performance 32-bit RISC microprocessor core, designed for cost-sensitive embedded applica-
tions, with particular emphasis on low power consumption, high code density, and high
performance.
The processor implements a Memory Protection Unit (MPU) and a fast and flexible interrupt con-
troller for supporting modern and real-time operating systems. The Secure Access Unit (SAU) is
used together with the MPU to provide the required security and integrity.
Higher computation capability is achieved using a rich set of DSP instructions.
The ATUC64/128/256L3/4U embeds state-of-the-art picoPower technology for ultra-low power
consumption. Combined power control techniques are used to bring active current consumption
down to 174µA/MHz, and leakage down to 220nA while still retaining a bank of backup regis-
ters. The device allows a wide range of trade-offs between functionality and power consumption,
giving the user the ability to reach the lowest possible power consumption with the feature set
required for the application.
The Peripheral Direct Memory Access (DMA) controller enables data transfers between periph-
erals and memories without processor involvement. The Peripheral DMA controller drastically
reduces processing overhead when transferring continuous and large data streams.
The ATUC64/128/256L3/4U incorporates on-chip Flash and SRAM memories for secure and
fast access. The FlashVault technology allows secure libraries to be programmed into the
device. The secure libraries can be executed while the CPU is in Secure State, but not read by
non-secure software in the device. The device can thus be shipped to end customers, who will
be able to program their own code into the device to access the secure libraries, but without risk
of compromising the proprietary secure code.
The External Interrupt Controller (EIC) allows pins to be configured as external interrupts. Each
external interrupt has its own interrupt request and can be individually masked.
The Peripheral Event System allows peripherals to receive, react to, and send peripheral events
without CPU intervention. Asynchronous interrupts allow advanced peripheral operation in low
power sleep modes.
The Power Manager (PM) improves design flexibility and security. The Power Manager supports
SleepWalking functionality, by which a module can be selectively activated based on peripheral
events, even in sleep modes where the module clock is stopped. Power monitoring is supported
by on-chip Power-on Reset (POR), Brown-out Detector (BOD), and Supply Monitor (SM). The
device features several oscillators, such as Phase Locked Loop (PLL), Digital Frequency
Locked Loop (DFLL), Oscillator 0 (OSC0), and system RC oscillator (RCSYS). Either of these
oscillators can be used as source for the system clock. The DFLL is a programmable internal
oscillator from 20 to 150MHz. It can be tuned to a high accuracy if an accurate reference clock is
running, e.g. the 32KHz crystal oscillator.
The Watchdog Timer (WDT) will reset the device unless it is periodically serviced by the soft-
ware. This allows the device to recover from a condition that has caused the system to be
unstable.
The Asynchronous Timer (AST) combined with the 32KHz crystal oscillator supports powerful
real-time clock capabilities, with a maximum timeout of up to 136 years. The AST can operate in
counter or calendar mode.
