User's Manual

L811-EA Module Hardware User Manual Page
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5.4.2 W_DISABLE# Signal.......................................................................................................................31
5.4.3 Android & Linux / Win8 & Win10 Dual Systems Switch Control Signal................................. 31
5.5 USB Interface...............................................................................................................................................32
5.5.1 USB Interface Definition................................................................................................................. 32
5.5.2 USB Interface Application.............................................................................................................. 33
5.6 UART Interface............................................................................................................................................33
5.6.1 UART Interface Description........................................................................................................... 33
5.6.2 UART Interface Application............................................................................................................34
5.7 USIM Interface.............................................................................................................................................34
5.7.1 USIM Pins......................................................................................................................................... 34
5.7.2 USIM Interface Design....................................................................................................................35
5.7.2.1 “Normally Closed” SIM Card Circuit Design.................................................................... 35
5.7.2.2 “Normally Open” SIM Circuit Design.................................................................................35
5.7.3 Highlights for USIM Design............................................................................................................36
5.7.4 USIM Hot-Plugging..........................................................................................................................36
5.7.4.1 Hardware Connection..........................................................................................................36
5.7.4.2 Software Setup..................................................................................................................... 37
5.8 Digital Audio................................................................................................................................................. 37
5.8.1 I2S Interface..................................................................................................................................... 37
5.8.2 PCM Mode Description...................................................................................................................38
5.9 I2C Interface.................................................................................................................................................38
5.10 Clock Interface.......................................................................................................................................... 39
5.11 Other Interfaces.........................................................................................................................................39
6 Electrical and Environmental Characteristic...................................................................................................... 40
6.1 Electrical Characteristic............................................................................................................................. 40
6.2 Environmental Characteristic.................................................................................................................... 40
7 RF Interface.............................................................................................................................................................41
7.1 RF PCB Design........................................................................................................................................... 41
7.1.1 Wire Routing Principle.................................................................................................................... 41
7.1.2 Impedance........................................................................................................................................ 42
7.2 Antenna Design........................................................................................................................................... 42
7.2.1 Main Antenna Design Requirements........................................................................................... 42