User guide

UC864-E/G/WD/WDU Hardware User Guide
1vv0300766a Rev.4
- 03/02/09
Reproduction forbidden without Telit Communications S.p.A’s. written authorization - All Rights Reserved. Page 46 of 78
Careful approach is needed to avoid latch-up on UC864-E/G/WD/WDU and the use
of this output line to power electronic devices must be avoided, especially for devices
that generate spikes and noise such as switching level translators, micro controllers,
failure in any of these condition can severely compromise the UC864-E/G/WD/WDU
functionality.
NOTE:
The input lines working at 2.6VCMOS can be pulled-up with 47KΩ resistors that can
be connected directly to the VAUX line. It is a must that they are connected as in this
example.
The preferable configuration is having external supply for the buffer.