ATMEGA32U4-MU Atmel, ATMEGA32U4-MU Datasheet - Page 4

• Manufacturer Part Number: ATMEGA32U4-MU
• Description: MCU AVR 32K FLASH 16MHZ 44-QFN
• Manufacturer: Atmel
• Series: AVR® ATmegar

Specifications of ATMEGA32U4-MU

• Core Processor: AVR
• Core Size: 8-Bit
• Speed: 16MHz
• Connectivity: I²C, SPI, UART/USART, USB
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 26
• Program Memory Size: 32KB (16K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 2.5K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 5.5 V
• Data Converters: A/D 12x10b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 44-VQFN
• Package: 44QFN EP
• Device Core: AVR
• Family Name: ATmega
• Maximum Speed: 16 MHz
• Operating Supply Voltage: 3.3|5 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 26
• Interface Type: EBI/I2S/SPI/TWI/USART/USB
• On-chip Adc: 12-chx10-bit
• Number Of Timers: 5
• For Use With: ATSTK524 - KIT STARTER ATMEGA32M1/MEGA32C1ATSTK600 - DEV KIT FOR AVR/AVR32ATAVRDRAGON - KIT DRAGON 32KB FLASH MEM AVRATSTK500 - PROGRAMMER AVR STARTER KIT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: ATMEGA32U4-16MU; ATMEGA32U4-16MU

5. Application Overview
4
AVR298
The USB audio application manages the data exchange between the PC and the PWM hard-
ware (speaker) and ADC hardware (microphone). When a sound is played on the PC, the USB
device receives a periodic unsynchronized OUT endpoints, and when the record microphone is
running then the USB device receives a periodic unsynchronized IN endpoints.
Figure 5-1.
During the USB enumeration, the USB device describes the frequency and the formats of the
audio data. In the demo, the data format used is the PCM, the speaker uses 16-bit mono at
32KHz, and the microphone uses 16-bit mono at 8KHz.
PC play
PC record
Application data exchange
OUT endpoint
PCM 16bits mono at 32KHz
PCM 16bits mono at 8KHz
IN endpoint
PWM
ADC
Speaker
Microphone
9bits mono at 32KHz
8bits mono at 8KHz
7820A–AVR–11/08