User's Manual Part 1

MC75 Hardware Interface Description
Strictly confidential / Draft
s
MC75_V00.190a Page 3 of 91 15.02.2005
Contents
0 Document History .........................................................................................................6
1 Introduction ...................................................................................................................8
1.1 Related Documents ...............................................................................................8
1.2 Terms and Abbreviations.......................................................................................9
1.3 Type Approval......................................................................................................12
1.4 Safety Precautions...............................................................................................14
2 Product Concept .........................................................................................................16
2.1 Key Features at a Glance ....................................................................................16
2.2 MC75 System Overview ......................................................................................19
2.3 Circuit Concept ....................................................................................................20
3 Application Interface...................................................................................................21
3.1 Power Supply.......................................................................................................22
3.1.1 Minimizing Power Losses ......................................................................22
3.1.2 Measuring the Supply Voltage V
BATT+
....................................................23
3.1.3 Monitoring Power Supply by AT Command ...........................................23
3.2 Power Up / Power Down Scenarios.....................................................................24
3.2.1 Turn on MC75 ........................................................................................24
3.2.1.1 Turn on MC75 Using Ignition Line IGT ..................................................24
3.2.1.2 Turn on MC75 Using the VCHARGE Signal ..........................................26
3.2.1.3 Reset MC75 via AT+CFUN Command ..................................................27
3.2.1.4 Reset MC75 in Case of Emergency via EMERG_RST..........................27
3.2.2 Turn off MC75 ........................................................................................28
3.2.2.1 Turn off MC75 Using AT Command.......................................................28
3.2.2.2 Leakage Current in Power Down Mode .................................................29
3.2.3 Automatic Shutdown ..............................................................................30
3.2.3.1 Temperature Dependent Shutdown.......................................................30
3.2.3.2 Temperature Control during Emergency call .........................................31
3.2.3.3 Undervoltage Shutdown if Battery NTC is Present ................................31
3.2.3.4 Undervoltage Shutdown if no Battery NTC is Present ...........................32
3.2.3.5 Overvoltage Shutdown...........................................................................32
3.3 Automatic EGPRS/GPRS Multislot Class Change ..............................................33
3.4 Charging Control..................................................................................................34
3.4.1 Battery Pack Requirements ...................................................................34
3.4.2 Batteries Recommended for Use with MC75.........................................35
3.4.3 Charger Requirements...........................................................................36
3.4.4 Implemented Charging Technique.........................................................36
3.4.5 Operating Modes during Charging.........................................................37
3.5 RTC Backup ........................................................................................................38
3.6 SIM Interface .......................................................................................................39
3.7 Serial Interface ASC0 ..........................................................................................40
3.8 Serial Interface ASC1 ..........................................................................................42
3.9 USB Interface ......................................................................................................43
3.9.1 Installing the USB Modem Driver...........................................................44
3.10 I
2
C Interface .........................................................................................................46
3.11 SD Memory Card Interface ..................................................................................47
3.12 Audio Interfaces...................................................................................................49
3.12.1 Speech Processing................................................................................50
3.12.2 Microphone Circuit.................................................................................50
3.12.2.1 Single-ended Microphone Input.............................................................50