User's Manual

UL865-N3G Hardware User Guide
1VV0301177 Rev 2– 2015-04-20
Reproduction forbidden without written authorization from Telit Communications S.p.A. - All Rights
Reserved. Page 6 of 70
Mod. 0805 2011-07 Rev.2
7.7. Antenna Requirements ..................................... 33
7.7.1. UL865-N3G V2 Antenna – PCB line Guidelines ................. 34
7.8. PCB Guidelines in case of FCC certification .............. 35
7.8.1. Transmission line design ................................... 35
7.8.2. Transmission line measurements ............................. 36
7.9. Antenna - Installation Guidelines ........................ 38
8. Logic level specifications .................................. 39
8.5. Reset signal ............................................. 40
9. USB Port .................................................... 41
9.1. USB 2.0 HS ............................................... 41
10. SPI Port .................................................... 42
10.5. SPI Connections ........................................ 42
11. Serial Ports ................................................ 43
11.1. MODEM SERIAL PORT 1 .................................... 43
11.2. MODEM SERIAL PORT 2 .................................... 45
11.3. RS232 level translation ................................ 46
12. Audio Section Overview ...................................... 48
13. General Purpose I/O ......................................... 48
13.1. GPIO Logic levels ...................................... 50
13.2. Using a GPIO Pad as INPUT .............................. 51
13.3. Using a GPIO Pad as OUTPUT ............................. 51
13.4. Indication of network service availability ............. 52
13.5. SIMIN detect function .................................. 53
13.6. RTC Bypass out ......................................... 53
13.7. SIM Holder Implementation .............................. 53
14. DAC and ADC section ......................................... 54
14.1. DAC Converter .......................................... 54
14.1.1. Description .............................................. 54
14.1.2. Enabling DAC ............................................. 55
14.1.3. Low Pass Filter Example .................................. 55
14.2. ADC Converter .......................................... 56