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AC75 Hardware Interface Description
Strictly confidential / Preliminary
s
AC75_HD_V00.202
Page 4 of 120
27.04.2006
3.7
Summary of State Transitions (Except SLEEP Mode).........................................49
3.8
RTC Backup ........................................................................................................50
3.9
SIM Interface .......................................................................................................51
3.9.1
Installation Advice..................................................................................52
3.10
Serial Interface ASC0 ..........................................................................................53
3.11
Serial Interface ASC1 ..........................................................................................55
3.12
USB Interface ......................................................................................................56
3.12.1
Installing the USB Modem Driver...........................................................57
3.13
I
2
C Interface .........................................................................................................59
3.14
SPI Interface ........................................................................................................61
3.15
Audio Interfaces...................................................................................................63
3.15.1
Speech Processing................................................................................64
3.15.2
Microphone Circuit .................................................................................64
3.15.2.1
Single-ended Microphone Input .............................................................65
3.15.2.2
Differential Microphone Input .................................................................66
3.15.2.3
Line Input Configuration with OpAmp ....................................................67
3.15.3
Loudspeaker Circuit...............................................................................68
3.15.4
Digital Audio Interface (DAI) ..................................................................69
3.15.4.1
Master Mode ..........................................................................................70
3.15.4.2
Slave Mode ............................................................................................72
3.16
GPIO Interface.....................................................................................................74
3.16.1
Using the GPIO10 Pin as Pulse Counter ...............................................74
3.17
Control Signals ....................................................................................................75
3.17.1
Synchronization Signal ..........................................................................75
3.17.2
Using the SYNC Pin to Control a Status LED........................................76
3.17.3
Behavior of the RING0 Line (ASC0 Interface only)................................77
3.17.4
PWR_IND Signal ...................................................................................77
4
Antenna Interface........................................................................................................78
4.1
Antenna Diagnostic..............................................................................................79
4.2
Antenna Connector..............................................................................................80
5
Electrical, Reliability and Radio Characteristics......................................................82
5.1
Absolute Maximum Ratings .................................................................................82
5.2
Operating Temperatures......................................................................................83
5.3
Storage Conditions ..............................................................................................84
5.4
Reliability Characteristics.....................................................................................85
5.5
Pin Assignment and Signal Description...............................................................86
5.6
Power Supply Ratings .........................................................................................93
5.7
Electrical Characteristics of the Voiceband Part..................................................96
5.7.1
Setting Audio Parameters by AT Commands ........................................96
5.7.2
Audio Programming Model ....................................................................97
5.7.3
Characteristics of Audio Modes .............................................................98
5.7.4
Voiceband Receive Path........................................................................99
5.7.5
Voiceband Transmit Path.....................................................................100
5.8
Air Interface .......................................................................................................101
5.9
Electrostatic Discharge ......................................................................................102
6
Mechanics..................................................................................................................103
6.1
Mechanical Dimensions of AC75.......................................................................103
6.2
Mounting AC75 to the Application Platform .......................................................105
6.3
Board-to-Board Application Connector ..............................................................106
7
Sample Application...................................................................................................109