User's Manual

HE910 Hardware User Guide
1vv0300925 Rev.28 – 2015-06-24
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved page 57 of 57
7.3.10 External LNA Enable
The HE910 is already provided by an internal LNA. In case the Application needs to include an
additional LNA stage, the module is provided by a digital signal usable to enable the power
supply of the external amplifier. The signal is set to High only when the GPS receiver is active.
The electrical characteristics of the GPS_LNA_EN signal are:
Level Min Max
Output high level 1.6V 1.9
Output low level 0V 0.2V
An example of GPS Antenna Supply circuit is shown in the following image:
NOTE:
The maximum DC voltage applicable to the ANT_GPS pin is 5V. In case this is exceeded, a
series capacitor has to be included in the design to avoid exceeding the maximum input DC
level.