MC45 Hardware Interface Description
P R E L I M I N A R Y
MC45_HD_01_V00.02a Page 3 of 90 12.08.2002
Contents
0 Version History........................................................................................................... 7
1 Introduction ................................................................................................................ 9
1.1 Related documents ............................................................................................. 9
1.2 Terms and abbreviations....................................................................................10
1.3 Type approval ....................................................................................................13
1.4 Safety precautions .............................................................................................15
2 Product concept........................................................................................................17
2.1 MC45 key features at a glance...........................................................................18
2.2 Circuit concept ...................................................................................................21
3 Application Interface.................................................................................................22
3.1 Operating modes ...............................................................................................23
3.2 Power supply .....................................................................................................25
3.2.1 Power supply pins on the board-to-board connector.............................25
3.2.2 Minimizing power losses.......................................................................26
3.2.3 Charging control...................................................................................27
3.2.3.1 Battery pack characteristics ......................................................28
3.2.3.2 Recommended battery pack .....................................................29
3.2.3.3 Implemented charging technique ..............................................30
3.2.3.4 Operating modes during charging .............................................31
3.2.3.5 Charger requirements ...............................................................32
3.3 Power up / down scenarios ................................................................................33
3.3.1 Turn on MC45 ......................................................................................33
3.3.1.1 Turn on MC45 using the ignition line /IGT (Power on)...............33
3.3.1.2 Timing of the ignition process ...................................................34
3.3.1.3 Turn on MC45 using the POWER signal...................................35
3.3.1.4 Turn on MC45 using the RTC (Alarm mode).............................35
3.3.2 Power saving........................................................................................36
3.3.2.1 No power saving (AT+CFUN=1)................................................36
3.3.2.2 NON-CYCLIC SLEEP mode (AT+CFUN=0)..............................36
3.3.2.3 CYCLIC SLEEP mode (AT+CFUN=5, 6, 7 and 8) .....................36
3.3.2.4 Timing of the /CTS signal in CYCLIC SLEEP modes ................37
3.3.2.5 Wake up MC45 from SLEEP mode...........................................39
3.3.3 Turn off MC45 ......................................................................................40
3.3.3.1 Turn off MC45 using AT command ...........................................40
3.3.3.2 Emergency shutdown using /EMERGOFF pin...........................41
3.3.4 Automatic shutdown .............................................................................42
3.3.4.1 Temperature dependent shutdown............................................42
3.3.4.2 Undervoltage shutdown if battery NTC is present .....................43
3.3.4.3 Undervoltage shutdown if no battery NTC is present ................43
3.3.4.4 Shutdown in the event of overvoltage .......................................44
3.3.5 Summary of state transitions ................................................................45
3.4 RTC backup.......................................................................................................46
3.5 Serial interfaces .................................................................................................47
3.6 Audio interfaces .................................................................................................49
3.6.1 Microphone circuit ................................................................................50