Table Of Contents - Quectel M12 Hardware Design

M12 Hardware Design
Table Index ........................................................................................................................................ 4
Figure Index ...................................................................................................................................... 5
0. Revision history ............................................................................................................................ 7
1. Introduction ................................................................................................................................... 8
1.1. Related documents .............................................................................................................. 8
1.2. Terms and abbreviations ...................................................................................................... 9
1.3. Safety cautions .................................................................................................................. 11
2. Product concept ........................................................................................................................... 13
2.1. Key features ...................................................................................................................... 13
2.2. Functional diagram ............................................................................................................ 15
2.3. Evaluation board ............................................................................................................... 16
3. Application interface ................................................................................................................... 17
3.1. Pins of module ................................................................................................................... 17
3.1.1. Pin assignment ......................................................................................................... 17
3.1.2. Pin description ......................................................................................................... 18
3.2. Operating modes ............................................................................................................... 23
3.3. Power supply ..................................................................................................................... 25
3.3.1. Power features of module ........................................................................................ 25
3.3.2. Decrease supply voltage drop .................................................................................. 25
3.3.3. Reference design for power supply ......................................................................... 26
3.3.4. Monitor power supply ............................................................................................. 27
3.4. Power up and power down scenarios ................................................................................ 27
3.4.1. Power on module using PWRKEY pin ................................................................... 27
3.4.2. Power down ............................................................................................................. 29
3.4.3. Restart module using PWRKEY pin ....................................................................... 32
3.5. Power saving ..................................................................................................................... 33
3.5.1. Minimum functionality mode .................................................................................. 34
3.5.2. SLEEP mode (slow clock mode) ............................................................................. 34
3.5.3. Wake up module from SLEEP mode ...................................................................... 34
c3.6. Summary of state transitions ........................................................................................... 35
3.7. RTC backup ...................................................................................................................... 35
3.8. Serial interfaces ................................................................................................................. 37
3.8.1. UART Port .............................................................................................................. 38
3.8.2. Debug Port ............................................................................................................... 41
3.8.3. UART3 Port ............................................................................................................ 42
3.8.4. UART Application .................................................................................................. 43
3.9. Audio interfaces................................................................................................................. 45
3.9.1. Decrease TDD noise and other noise ...................................................................... 46
3.9.2. Microphone interfaces configuration ....................................................................... 46
3.9.3. Receiver and speaker interface configuration .......................................................... 47
3.9.4. Earphone interface configuration ............................................................................ 49
M12_Hardware_Design_V3.3
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