AT43USB325_05 Datasheet, PDF (1/109 Pages) ATMEL Corporation – Multimedia USB Keyboard Controller with Embedded Hub

Features
• AVR^® 8-bit RISC Microcontroller with 83 ns Instruction Cycle Time
• USB Hub with One Attached and Four External Ports
• USB Keyboard Function with Four Programmable Endpoints
• 16 KB Program Memory, 512-Byte Data SRAM
• 32 x 8 General-purpose Working Registers
• 42 Programmable I/O Port Pins
• Support for 20 x 8 Keyboard Matrix
• Keyboard Scan Inputs with Pull-up Resistor
• Four LED Driver Outputs
• One 8-bit Timer/Counter with Separate Pre-scaler
• One 16-bit Timer/Counter with Separate Pre-scaler and Dual 8-, 9- or 10-bit PWM
• External and Internal Interrupt Sources
• Programmable Watchdog Timer
• 6-MHz Oscillator with On-chip PLL
• 5V Operation with On-chip 3.3V Power Supply
• 64-lead LQFP Package
1. Description
The Atmel AT43USB325 is an 8-bit microcontroller based on the AVR RISC architec-
ture. By executing powerful instructions in a single clock cycle, the AT43USB325
achieves throughputs approaching 12 MIPS. The AVR core combines a rich instruc-
tion set with 32 general-purpose working registers. All 32 registers are directly
connected to the ALU allowing two independent registers to be accessed in one single
instruction executed in one clock cycle. The resulting architecture is more code effi-
cient while achieving throughputs up to ten times faster than conventional CISC
microcontrollers.
The AT43USB325 features an on-chip 16-Kbyte program memory and
512 bytes of data memory. It is supported by a standard set of peripherals such as
timer/counter modules, watchdog timer and internal and external interrupt sources.
The major peripheral included in the AT43USB325 is the USB Hub with an embedded
function and GPIO ports designed for use in a keyboard controller. The embedded
function has 4 endpoints that makes the AT43USB325 extremely suitable for key-
boards supporting the consumer page as described in the “USB Usage Tables”.
The AT43USB325 comes in two versions. The program memory of the
AT43USB325E is an SRAM that is automatically written from an external serial
EEPROM during power on. The AT43USB325M has a masked ROM program mem-
ory. The two versions are pin, function and binary compatible.
Multimedia
USB Keyboard
Controller with
Embedded Hub
AT43USB325
3355C–USB–4/05