User's Manual

GC864 Hardware User Guide
1vv0300733 Rev. 0 - 12/06/06
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Right reserved page 26 of 68
6.2 5V UART level translation
If the OEM application uses a microcontroller with a serial port (UART) that works at a voltage different
from 2.8 - 3V, then a circuitry has to be provided to adapt the different levels of the two sets of signals.
As for the RS232 translation there are a multitude of single chip translators, but since the translation
requires very few components, then also a discrete design can be suited. For example a possible
inexpensive translator circuit for a 5V driver can be:
and for a 5V receiver: