User ManualTable of ContentsDocument history7Introduction9Related documents9Terms and abbreviations10Type approval13Safety precautions15Product concept17MC55/56 key features at a glance18Circuit concept21Application Interface22Operating modes23Power supply25Power supply pins on the board-to-board connector25Minimizing power losses26Monitoring power supply26Power up / down scenarios27Turn on MC55/5627Turn on MC55/56 using the ignition line /IGT (Power on)28Timing of the ignition process29Turn on MC55/56 using the POWER signal30Turn on MC55/56 using the RTC (Alarm mode)30Turn off MC55/5632Turn off MC55/56 using AT command32Emergency shutdown using /EMERGOFF pin33Automatic shutdown34Temperature dependent shutdown34Temperature control during emergency call35Undervoltage shutdown if battery NTC is present35Undervoltage shutdown if no battery NTC is present36Overvoltage shutdown36Automatic GPRS Multislot Class change37Charging control38Battery pack characteristics39Implemented charging technique41Operating modes during charging42Charger requirements43Power saving44No power saving (AT+CFUN=1)44NON-CYCLIC SLEEP mode (AT+CFUN=0)44CYCLIC SLEEP mode (AT+CFUN=5, 6, 7, 8)45CYCLIC SLEEP mode AT+CFUN=945Timing of the /CTS signal in CYCLIC SLEEP modes45Wake up MC55/56 from SLEEP mode47Wake-up via /RTS0 and RTS1 (if AT+CFUN=0 or AT+CFUN=9)48Summary of state transitions (except SLEEP mode)49RTC backup50Serial interfaces51Features supported on first and second serial interface52Audio interfaces54Microphone circuit55Speech processing56DAI timing56SIM interface58Requirements for using the CCIN pin59Design considerations for SIM card holder60Control signals61Inputs61Outputs62Synchronization signal62Using the SYNC pin to control a status LED63Behavior of the /RING0 line (ASC0 interface only)65Antenna interface66Antenna installation66Antenna pad68Suitable cable types68Hirose antenna connector69Electrical, reliability and radio characteristics73Absolute maximum ratings73Operating temperatures73Electrical specifications of the application interface74Power supply ratings79Current consumption during transmit burst80Electrical characteristics of the voiceband part85Setting audio parameters by AT commands85Audio programming model86Characteristics of audio modes87Voiceband receive path88Voiceband transmit path89Air interface90Electrostatic discharge91Reliability characteristics92Mechanics93Mechanical dimensions of MC55/5693Mounting MC55/56 onto the application platform95Board-to-board connector96Mechanical dimensions of the Hirose DF12 connector97Adapter cabling97Reference Approval98Reference Equipment for Type Approval98Compliance with FCC Rules and Regulations (MC55 only)99Compliance with FCC Rules and Regulations (MC56 only)100Design example101List of parts and accessories103Size: 1.66 MBPages: 104Language: EnglishOpen manual