User Manual
Table Of Contents
- Confidential Material
 - Copyright
 - Revision History
 - Trademarks Notice
 - Contents
 - Preface
 - Introduction
 - Hardware Interface Description
 - Electrical and Environmental Specifications Absolute Maximum Ratings
 - Mechanical Design
 - Antenna Interface
 
G610 GPRS Module Hardware User Manual                  Page 30 of 47 
through the microphone input signals and then are amplified by the G610's internal audio amplifiers.   
To minimize the audio noise and improve the audio performance the microphone and speaker 
signals must be designed with sufficient protection from surrounding noises.   
The following guidelines should be followed to achieve best audio performance:   
  Reference the microphone input circuits to the G610 AGND interface signal.   
  If using single-ended audio outputs, they should be referenced to the G610 AGND 
interface signal.   
  Keep the audio circuits away from the antenna.   
  Use RF filtering capacitors on the audio signals.   
  The audio signals should not be routed adjacent to digital signals.   
  Isolate the audio signals by a surrounding ground plane or shields.   
  Filter internal supplies and signals that may indirectly affect the audio circuits, from noises 
and voltage drops.   
3.9.6  Switch Audio Channel by IO 
The G610 support switch audio channel by IO pin. The default level of this pin is high. This IO 
pin is took effect under 1st channel is activated. 
When the IO is pulled low, the audio channel will be switched from 1st channel   to 2nd channel 
automatically. When the IO level is back to High, the audio channel will be back to 1st channel.   
If the audio 2nd channel is activated, this PIN will not do any effect at all. 
G610 Pin#  G610 Signal name  Description 
47  HS_DET 
  1st channel is activated. 
Level = Low, the 2nd channel is activated 
Level = High, back to the 1st channel 
Notes:  After the MAPATH command was switch the audio channel, this PIN will not do any 
effect at all. 
3.10 A/D Interface   
The G610 includes 3 Analog to Digital Converter (ADC) (2 ADC and 1 BATT ADC ) signals with 
12-bit resolution, for environmental and electrical measurements. The ADC signals accept an 
analog DC voltage level on their inputs and convert it to a 12-bit digital value for further processing 
by G610 or the user application.   
In Idle mode, the ADC input is sampled consecutive times by sampling time interval, and the 










