User Manual
 GM862-QUAD / PY Hardware User Guide 
  1vv0300748 Rev. 5 - 20/09/07  
Reproduction forbidden without Telit Communications S.p.A. written authorization - All Rights Reserved    page 14 of 68 
4.2  GSM Antenna - Installation Guidelines 
•  Install the antenna in a place covered by the GSM signal. 
•  The Antenna must be installed to provide a separation distance of at least 20 cm from all persons 
and must not be co-located or operating in conjunction with any other antenna or transmitter; 
•  Antenna shall not be installed inside metal cases 
•  Antenna shall be installed also according Antenna manufacturer instructions. 
4.3  Logic level specifications 
Where not specifically stated, all the interface circuits work at 2.8V CMOS logic levels. The following 
table shows the logic level specifications used in the Telit GM862-QUAD/PY interface circuits: 
     Absolute Maximum Ratings -Not Functional 
Parameter  Min  Max 
Input level on any 
digital pin when on 
-0.3V  +3.6V 
Input voltage on 
analog pins when on
-0.3V  +3.0 V 
Voltage on Buffered 
pins 
-0.3V  25V 
Operating Range - Interface levels (2.8V CMOS) 
Level  Min  Max 
Input high level  2.1V  3.3V 
Input low level  0V  0.5V 
Output high level  2.2V  3.0V 
Output low level  0V  0.35V 
For 2,0V signals: 
     Operating Range - Interface levels (2.0V CMOS) 
Level  Min  Max 
Input high level  1.6V  3.3V 
Input low level  0V  0.4V 
Output high level  1,65V  2.2V 
Output low level  0V  0.35V 










