Download GC864 Hardware User Guide

GC864 Hardware User Guide
1vv0300694 Rev. 3 - 07/02/06
Contents
1
Overview ...........................................................................................................................4
2
Hardware Commands ......................................................................................................5
2.1
Turning ON the GE864 ...........................................................................................................5
2.2
Turning OFF the GE864 ........................................................................................................7
2.2.1
2.3
3
Hardware shutdown..........................................................................................................................7
Hardware Unconditional Reboot ...........................................................................................7
Power Supply ...................................................................................................................9
3.1
Power Supply Requirements .................................................................................................9
3.2
General Design Rules ..........................................................................................................10
3.2.1
Electrical design Guidelines........................................................................................................... 10
3.2.1.1 + 5V input Source Power Supply Design Guidelines ................................................................ 10
3.2.1.2 + 12V input Source Power Supply Design Guidelines .............................................................. 12
3.2.1.3 Battery Source Power Supply Design Guidelines ..................................................................... 13
3.2.1.4 Battery Charge control Circuitry Design Guidelines .................................................................. 13
3.2.2
Thermal Design Guidelines ........................................................................................................... 15
3.2.3
Power Supply PCB layout Guidelines ........................................................................................... 16
4
5
6
Antenna...........................................................................................................................17
4.1
Antenna Requirements ........................................................................................................17
4.2
Antenna PCB line Guidelines ..............................................................................................18
4.3
Antenna installation Guidelines ..........................................................................................19
Serial Port .......................................................................................................................20
5.1
RS232 level translation ........................................................................................................22
5.2
5V UART level translation....................................................................................................24
Microphone.....................................................................................................................26
6.1
Microphone line Characteristic and requirements ............................................................26
6.2
General Design Rules ..........................................................................................................29
6.3
Microphone Biasing .............................................................................................................29
6.3.1
6.3.2
6.4
Balanced Microphone biasing........................................................................................................ 30
Unbalanced Microphone biasing ................................................................................................... 31
Microphone buffering...........................................................................................................32
6.4.1
6.4.2
Buffered Balanced Mic................................................................................................................... 32
Buffered Unbalanced (Single Ended) Mic. .................................................................................... 34
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