Circuit Description
AX−SFEU and AX−SFEU−API are ultra−low power
single chip solutions for a node on the Sigfox network with
both up− and down−link functionality. The AX−SFEU chip
is delivered fully ready for operation and contains all the
necessary firmware to transmit and receive data from the
Sigfox network in Europe. It connects to the customer
product using a logic level RS232 UART. AT commands are
used to send frames and configure radio parameters.
The AX−SFEU−API variant is intended for customers
wishing to write their own application software based on the
AX−SF−LIB−1−GEVK library.

Features
Functionality and Ecosystem
• Sigfox up−link and down−link functionality controlled
by AT commands or API
• The AX−SFEU and AX−SF−API ICs are part of a
whole development and product ecosystem available
from ON Semiconductor for any Sigfox requirement.
Other parts of the ecosystem include
♦ Ready to go development kit
DVK−SFEU−[API]−1−GEVK including a 2 year
Sigfox subscription
♦ Sigfox Ready® certified reference design for the
AX−SFEU and AX−SFEU−API ICs
♦ AX−SF10−MINI21−868−B1 and
AX−SF10−ANT21−868−B1, Sigfox compliant SMT
modules based on AX−SFEU with 50  pads or chip
antenna. Not available for AX−SFEU−API

General Features
• QFN40 5 mm x 7 mm package
• Supply range 2.1 − 3.6 V
• −40°C to 85°C
• Temperature sensor
• Supply voltage measurements