This is an 8-bit microcontroller based on the AVR RISC architecture. It has an instruction cycle time of 83ns and can be used as a USB hub. It also has USB keyboard functionality, 16KB of program memory and 512 bytes of data storage.
The AT43USB326 is an 8‑bit AVR® RISC microcontroller designed for multimedia USB keyboard applications. It integrates a USB hub with one attached and two external ports, a keyboard function with three programmable endpoints, and a full set of peripherals including a timer/counter, watchdog timer, and LED drivers.
The device provides 16 KB of on‑chip program memory, 512 bytes of data SRAM, 32 general‑purpose working registers, and 32 programmable I/O port pins supporting an 18 × 8 keyboard matrix. It operates at 5 V with an on‑chip 3.3 V regulator and is supplied in a 48‑lead LQFP package.
| Core Architecture | AVR® 8‑bit RISC |
|---|---|
| Instruction Cycle Time | 83 ns |
| USB Hub Ports | 1 attached + 2 external |
| USB Keyboard Endpoints | 3 programmable |
| Program Memory | 16 KB |
| Data SRAM | 512 bytes |
| General‑purpose Registers | 32 × 8 bits |
| Programmable I/O Pins | 32 |
| Keyboard Matrix Support | 18 × 8 |
| LED Driver Outputs | 4 |
| Timer/Counter | 8‑bit with separate prescaler |
| Watchdog Timer | Programmable |
| Oscillator | 6 MHz with on‑chip PLL |
| Operating Voltage | 5 V (on‑chip 3.3 V regulator) |
| Package | 48‑lead LQFP |
The device operates at 5 V and includes an on‑chip 3.3 V power supply.
It provides 32 programmable I/O port pins.
The microcontroller contains 16 KB of program memory.
The hub has one attached port and two external ports.