WA_DEV_W218_PTS_002
Rev 005
Page 8 of 109
Product Technical Specification &
Customer Design Guidelines
SPI Bus for Debug Trace ONLY ..................................................................................................... 35
Pin Description ............................................................................................................................. 35
SPI Waveforms ................................................................................................................................... 35
Main Serial Link (UART) ................................................................................................................. 38
Features ......................................................................................................................................... 38
Pin Description ............................................................................................................................. 38
5-wire serial interface hardware design: ........................................................................................... 39
4-wire serial interface hardware design: ........................................................................................... 39
2-wire serial interface hardware design: ........................................................................................... 39
Application .................................................................................................................................... 40
V24/CMOS possible design ............................................................................................................... 41
SIM Interface ...................................................................................................................................... 44
Features ......................................................................................................................................... 44
Pin Description ............................................................................................................................. 45
Application .................................................................................................................................... 46
SIM socket connection ....................................................................................................................... 46
General Purpose Input/Output ....................................................................................................... 47
Pin Description ............................................................................................................................. 47
Analog to Digital Converter ............................................................................................................. 48
Features ......................................................................................................................................... 48
Pin Description ............................................................................................................................. 48
Analog Audio Interface .................................................................................................................... 49
Microphone Features ................................................................................................................... 49
Electrical Characteristics ................................................................................................................... 49
Speaker Features .......................................................................................................................... 50
Speakers Outputs Power ................................................................................................................... 50
Pin Description ............................................................................................................................. 51
Application .................................................................................................................................... 52
Microphone ......................................................................................................................................... 52
Recommended Components ............................................................................................................. 53
Recommended Components ............................................................................................................. 55
Speaker SPKP and SPKN .................................................................................................................. 56
Design Recommendation ............................................................................................................ 56
General ................................................................................................................................................ 56
Recommended Microphone Characteristics .................................................................................... 57
Recommended Speaker Characteristics .......................................................................................... 57
Recommended Filtering Components .............................................................................................. 57
Audio Track and PCB Layout Recommendation ............................................................................. 59
Pulse-Width Modulators (PWMs) ................................................................................................... 62
Features ......................................................................................................................................... 62
Pin Description ............................................................................................................................. 62
Application .................................................................................................................................... 62
BUZZER Output ................................................................................................................................. 64
Features ......................................................................................................................................... 64
Pin Description ............................................................................................................................. 64
Application .................................................................................................................................... 65
Calculations of the Low Filter: ........................................................................................................... 66
