Briefly introduced: Olimexino-32U4

The Olimexino-32U4 is an Arduino Leonardo like development board with an Atmel ATmega32U4 processor, that also takes over the USB communication. The manufacturer is the company OLIMEX Ltd. from Bulgaria.



The Board is well suited for applications without an external power supply, as it has a LiPo battery terminal with automatic charging function. This means that if an external power supply and a battery is connected – the circuit is running while the battery is charging – then later simply disconnect the external power supply and the board will continue to operate seamlessly with the accumulator.

Olimex has the Olimexino-32U4, as almost all development boards from the same company, equipped with a UEXT connector, which combines all of the communication channels, such as I²C, SPI, and the serial port on one plug. A practical matter, which, however, has a drawback, since some Arduino shields, such as the Network Shield, unfortunately, do not fit without modification.


  • ATMEL ATmega32U4 processor with 32KB Flash, 2.5 KB of SRAM, 1KB EEPROM, clocked at 16MHz
  • 12 analog inputs (6 on the digital pins)
  • 20 digital inputs or outputs, 7 with PWM support
  • Mini-USB port, fully supported by the ATmega32U4
  • the board can simulate a mouse or keyboard via the USB port through the HID protocol
  • I2C support
  • LiPo battery terminal with automatic charging with external power supply
  • Power supply 7-12V DC
  • programmable with the Arduino software

Circuits and projects with the Olimexino-32U4:

Sensors: Temperature & humidity measurements with the DHT11
Mood lamp with a digital RGB LED Strip (WS2811), an Arduino, acrylic glass and a few parts from the hardware store


eBay: Olimexino 32U4
Amazon: Olimexino 32U4