User's Manual
HC864-AUTO Hardware User Guide
1vv0300946 Rev.4 – 2012-12-27
Reproduction forbidden without written authorization from Telit Communications S.p.A. - All Rights
Reserved. Page 6 of 77
5.2.1.2.
+ 12V Input Source Power Supply Design Guidelines ........ 30
5.2.1.3.
Battery Source Power Supply Design Guidelines ............ 32
5.2.2.
Thermal Design Guidelines.................................... 33
5.2.3.
Power Supply PCB Layout Guidelines........................... 34
6.
Antenna(s) ................................................... 36
6.1.
GSM/WCDMA Antenna Requirements ............................ 36
6.2.
GSM/WCDMA Antenna - Installation Guidelines ............... 37
6.3.
GPS/GNSS and RX diversity Antenna Requirements ............ 37
6.3.1.
GPS/GNSS Antenna Requirements................................ 37
6.3.2.
RX Diversity Antenna Requirements............................ 38
6.4.
GPS/GNSS Antenna Installation Guidelines .................. 38
7.
Logic Level Specifications ................................... 39
7.1.
Reset Signal .............................................. 41
8.
Serial Ports ................................................. 42
8.1.
Modem Serial Port ......................................... 42
8.2.
RS232 Level Translation ................................... 44
8.3.
5V UART Level Translation ................................. 47
9.
Audio Section ................................................ 49
10.
USB Port..................................................... 50
11.
General Purpose I/O ......................................... 51
11.1.
Logic Level Specifications ............................... 53
11.2.
Using a GPIO Pad as Input ................................ 54
11.3.
Using a GPIO Pad as Output ............................... 54
11.4.
Using the Alarm Output GPIO6 ............................. 55
11.5.
Using the Temperature Monitor Function ................... 56
11.5.1.
............................................................
Short Description
56
11.5.2.
...................................................................
Allowed GPIO
56
11.6.
Indication of Network Service Availability ............... 57
11.7.
RTC Bypass Out ........................................... 58
11.8.
VAUX1 Power Output ....................................... 58