AT43USB355E-AC

Overview

The AT43USB355E is a full-speed USB AVR-based microcontroller featuring an embedded USB 1.1 compliant hub and function controller. It integrates a high-performance, low-power AVR RISC core with 24K bytes of downloadable SRAM program memory and 1K byte internal SRAM. The device includes 27 programmable I/O pins, a 12-channel 10-bit ADC, SPI interface, and two PWM outputs. It operates at 5V with on-chip 3.3V regulators and utilizes a 64-lead LQFP package.

Feature Summary

• Fully programmable USB 1.1 hub with 2 external and 1 attached downstream port
• Full-speed USB function controller with 4 endpoints
• AVR RISC microcontroller with 24K bytes downloadable SRAM and 1K byte internal SRAM
• 12-channel 10-bit A-to-D converter and dual PWM outputs

Applications

• Game controllers
• Joysticks
• Racing wheels
• Gamepads

Procurement Notes

Verify the specific ordering suffix to confirm the package type and temperature range. Ensure compatibility with existing development tools such as C compilers and in-circuit emulators designed for Atmel AVR microcontrollers. Confirm that the SRAM-based firmware loading mechanism aligns with the system's power-on reset requirements.

Selection Notes

Select the AT43USB355E when firmware flexibility is required, as it uses downloadable SRAM instead of masked ROM. This variant automatically loads code from external serial Flash or EEPROM during power-on reset. It is pin and function compatible with the AT43USB355M, allowing for design adjustments based on production volume and update needs.

Part Context

This component belongs to the Atmel AT43USB355 family, which combines USB connectivity with microcontroller capabilities. The 'E' suffix denotes the version with SRAM program memory, distinguishing it from the 'M' version which stores firmware in masked ROM. Both versions share identical pinouts and functional characteristics.

Replacement Considerations

The AT43USB355M serves as a direct replacement if firmware updates are not required, offering pin and function compatibility. Designers must ensure that the target application does not rely on runtime firmware modifications when switching to the ROM-based variant.