How Does Atmega32u4 Feature In Circuit Board Field?

Will is proficient in electronic components, PCB production process and assembly technology, and has extensive experience in production supervision and quality control. On the premise of ensuring quality, Will provides customers with the most effective production solutions.
How Does Atmega32u4 Feature In Circuit Board Field

When consumer electronics devices spring up in recent decades, the demand for Atmega32u4 dramatically increases. This text will explore what it is, how it features, and where it is applied.

What Is Atmega32u4?

The ATmega32U4 is a powerful, user-friendly, and highly integrated micro-controller, which is widely applied in embedded systems requiring USB connectivity and complex communications. The ATMega32U4 is a low-power 8-bit AVR RISC-based micro-controller distinguished by 2.5KB SRAM, 1KB EEPROM, 32KB self-programming flash program memory, 12-channel 10-bit A/D-converter, USB 2.0 full-speed/low-speed device, and JTAG interface for on-chip-debug.

ATmega32U4 Datasheet

Category 8-bit AVR Micro-controller Program Memory Type Flash
Program Memory Size 32KB CPU Speed (MIPS/DMIPS) 16
SRAM 2560B Data EEPROM/HEF 1024bytes
Digital Communication Peripherals 1-UART, 2-SPI, 1-I2C Capture/Compare/PWM Peripherals 2 Input Capture, 2 CCP, 12PWM
Timers 2 x 8-bit, 2 x 16-bit Number of Comparators 1
Number of USB Modules 1, Full Speed Temperature Range -40 to 85°C
Operating Voltage Range 2.7 to 5.5V Pin Count 44

Features of Atmega32u4

Versatile Pinout

Versatile Pinout

Pin No. Pin Name Pin No. Pin Name
1 (INT6/AINO)PE6 23 GND1
2 UVcc 24 AVCC
3 D- 25 (ICP1/ADC8)PD4
4 D+ 26 (T1/#OC4D/ADC9)PD6
5 UGnd 27 (T0/OC4D/ADC10)PD7
6 UCap 28 (ADC11/PCINT4)PB4
7 VBus 29 (PCINT5/OC1A/#OC4B/ADC12)PB5
12 (PCINT7/OC0A/OC1C/#RTS)PB7 34 Vcc1
13 RESET 35 GND2
14 Vcc 36 (ADC7/TDI)PF7
15 GND 37 (ADC6/TDO)PF6
16 XTAL2 38 (ADC5/TMS)PF5
17 XTAL1 39 (ADC4/TCK)PF4
18 (OCOB/SCL/INT0)PD0 40 (ADC1)PF1
19 (SDA/INT1)PD1 41 (ADC0)PF0
20 (RX D1/AIN1/INT2)PD2 42 AREF
21 (TXD1/INT3)PD3 43 GND3
22 (XCK1/#CTS)PD5 44 AVCC1

To sum up, there are total 44 versatile pins equipped on it. Two of them can be used as VCC and four of them can be used as GND. Fourteen pins can serve as digital function, including seven pins for PWM. More and more, ATmega32U4 comes with one MOSI pins, one MISO pins and one HWB pins. They allow user’s access and loading program. Further, it can be even used as common GPIO. Last, it has one UART output, four SPI and one I2C pin.

What Is the Current Consumption of ATmega32u4?

ATmega32u4 is an 8-bit micro-controller, which is mainly applied in low power consumption. It has a 16MHz crystal. Measuring by a multi-meter, the power consumption is at 40mA, which is very suitable for tiny device such as electronics toys and USB controller. What’ more, it is equipped with a USB interface for direct connection to PC.

Does ATmega32u4 Come With Bootloader?

There is no Bootloader in ATmega32u4, but it has excellent compatibility of bootloader programming. Meanwhile, the programming steps is not so complicated.

  1. Prepare USBASP downloader.
  2. Install USBASP driver.
  3. Connect USBASP to ATmega32u4. Leave three NC pins alone.
  4. Plug USBASP into computer and open progisp software. In the operating interface, select chip first. Then click RD Button. Don’t forget to click the … button to set up fuse position, since this button is at a unimpressive corner. After click import flash for loading firmware, you can click the automatic programming button. There will be a reminder of successful programming after a while.

Two Packages Available

It comes with two types of packages, ATMEGA321A-MU for QFN and ATMEGA32U4-AU for TQFP. The biggest difference between them is pin distance and shape. QFN is flat and comes with pins that are soldering on the bottom, while TQFP is a rectangle package with 0.5mm-interval pins. Though they are various in packages and pins, their functions are the same.

Excellent Flash Memory

It has 32KB flash memory, 2.5KB SRAM and 1KB EEPROM. When data store in flash memory, device performs quickly. Additionally, large flash memory not only greatly reduces I/O bottleneck which waste the life cycle of CPU, but also results in bad performance of specific function.

Application in Circuit Board Field

  • Development board: Arduino Micro, based on ATmega32U4, is co-developed with Adafruit. It has 20 digital input/output pins (7 of which can be used as PWM outputs and 12 as analog inputs), 16 MHz crystal oscillator, micro USB connection, ICSP head, and reset button. Moreover, its size is properly match to breadboard. Just connect it to your computer by micro USB cable, it is completely ready for starting using. The ATmega32U4 has built-in USB communication, eliminating the need for an auxiliary processor. This allows the Micro to appear as a mouse and keyboard on connected computers, in addition to the function of analog (CDC) serial and COM ports.
  • Consumer Electronics PCB: Its good performance and abundant resource contributes to smart and efficient function. Arduino ATmega32u4 can be used in Set-top box, smart loudspeaker, digital camera and game pad board.
  • Telecom PCB: Thanks to its USB interface and communication interface, the speed and stability of data delivery and process are greatly improved. Thus, it enjoys great popularity in wifi router and wireless base station board.
  • Automatic industrial PCB: Quick calculation of the device fits it into PLC controllers, industrial metering device and smart electric machine controller PCB.


Undoubtedly, Atmega32u4 is an useful device and gain huge popularity in integrated circuits, with its satisfying features. And still, we believe that this trend will not fade away in the future as long as smart consumer electronics keep strong in the market. If you would like to engage in this hopeful field, please feel free to contact us.

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Will is proficient in electronic components, PCB production process and assembly technology, and has extensive experience in production supervision and quality control. On the premise of ensuring quality, Will provides customers with the most effective production solutions.
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