the replacement for USB megaAVR U2
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– Immutable boot
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– 256B of boot row
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– Auto-tuning for improved internal oscillator accuracy [OSCHF, 32MHz]
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• External high-frequency crystal oscillator (XOSCHF) with clock failure detection
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– One USB 2.0 full-speed device(1)
• Optional internal 3.3V voltage regulator
• OSCHF oscillator can be tuned to the USB start-of-frames (SOFs) for crystal-less operation
• 16 endpoint addresses each with one input and one output endpoint for up to 31 endpoints
• Multi-Packet transfer for reduced interrupt load and software intervention
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• I/O and Packages:
– Up to 25 (24) programmable GPIO (I/O) pins
– 32-pin VQFN 5x5 mm and TQFP 7x7 mm
– 28-pin VQFN 4x4 mm, SPDIP and SSOP
– 20-pin SOIC – 14-pin SOIC
• Temperature Ranges:
– Industrial: -40°C to +85°C
– Extended: -40°C to +125°C
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The first AVRxt with a USB device controller.
immutable boot - rare for an AVR
Catching up to the USB PIC.
edit : AVR DU product brief was archived via the following post
USB or USB OTG Host: AT90USB1287 Only? | AVR Freaks