That means | Telit Wireless Solutions GE863-QUAD, GE863-PY specs

GE863-QUAD

GE863-PY

1vv0300715 Rev. 1 - 19/09/06

TIP: definition of the nominal sensitivity of the microphone lines .

The nominal sensitivity of the microphone lines indicates the voltage level on the GE863-QUAD / PY pins present during "normal spoken" conditions.

For a handset , the "normal spoken” conditions take place when the talker mouth is 7cm far from the microphone ; under these conditions the voice will produce an acoustic pressure of -4,7dBPa @1kHz on the microphone membrane .

TIP: electrical equivalent signal and operating voice levels .

At "normal spoken" conditions, a microphone having the suggested nominal sensitivity of - 45dBVrms/Pa , will produce

the electrical equivalent signal :

MicLevel = ( -45) + (-4.7) = -49.7 dBVrms

that means :

MicVoltage = 10 ( -49.7 / 20 ) = 3.3* 10 -3Vrms

During a call, this level varies according to the volume of the talker voice; usually the following rough thumb rule for the dynamic range may be used :

1)the talker is screaming . This is the strongest voice level condition: the signal increases by +20dB;

2)the talker is whispering. This is the lowest voice level condition: the voice level decreases by – 50dB.

These changes must be considered for designing the external microphone amplifier.

TIP: example of external microphone amplifier calculation .

Let’s suppose to use the 1stdifferential microphone path .In this case the maximum differential input voltage to “Mic_MT” lines is 365mVrms(1,03Vpp) corresponding to –8,76dBV.

Now we can calculate the maximum voltage gain of an external microphone amplifier GA :

[(MicLevel + 20dB)+ GA ]= −8,76dBV [− 49,7 + 20 + GA ]= −8,76

−40,9 + 20 = −GA

GA = 20,94dB			you can set GA= +20dB to use standard resistor values .

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Telit Wireless Solutions GE863-QUAD, GE863-PY manual That means, You can set GA= +20dB to use standard resistor values

Contents

GE863-QUAD GE863-PY Hardware User Guide Contents 10.2 10.110.3 10.4 12.1 13.113.2 This document is relating to the following products Overview PIN-OUT GE863 module connections Pin Signal Function Internal Type Pull up Pin Signal Function Internal Type Pins Layout Turning on the GE863-QUAD/PY Hardware Commands Turning off of the device can be done in two ways Turning OFF the GE863-QUAD/PY Hardware shutdown Hardware Unconditional Reboot GE863-QUAD Power Supply 1Power Supply RequirementsGE863-QUAD/PY power requirements are Electrical design Guidelines 2General Design Rules An example of linear regulator with 5V input is 1.2 + 12V input Source Power Supply Design Guidelines An example of switching regulator with 12V input is Battery Source Power Supply Design Guidelines Battery Charge control Circuitry Design Guidelines Thermal Design Guidelines Power Supply PCB layout Guidelines GSM Antenna Requirements Antenna GSM Antenna installation Guidelines Serial PortsGSM Antenna PCB line Guidelines Level Min Max Absolute Maximum Ratings -Not Functional Parameter Min Max Number Pad Number Signals in the Uart connector on the EVK are17-28-36 Ground 45-48-50-56 Clear to Send Output from the GE863-QUAD/PY that It is available on the following pins 2MODEM Serial Port 2 Python Debug3RS232 level translation An example of level translation circuitry of this kind is 5V Uart level translation GE863-QUAD Audio Section Overview GM863-GPS Echo canceller type Handset Microphone Paths Characteristic and RequirementsEcho canceller type Car kit hands-free + 20dB You can set GA= +20dB to use standard resistor values That means TIP environment consideration Other considerations General Design Rules Balanced Microphone Biasing Microphone Biasing Unbalanced Microphone Biasing GE863-QUAD Microphone Buffering Buffered Balanced MicSample circuit can be Buffer gain is given by the formula Gain = RR604605 = RR607606 Buffered Unbalanced Single Ended Microphone Buffer bandwidth at -3dB shall be 4KHz Freq . = 2π * R719* C726 2π * R711* C727 GE863-QUAD Short description Output Lines Speaker SW volume level step Number of SW volume steps Output Lines Characteristics Noise Filtering Handset Earphone Design An example of internal Ear amplifier could be Hands-Free Earphone Low Power Design Car Kit Speakerphone Design Short Description Evaluation Kit for Telit Modules EVK2 @ 350mW 2 EVK2 Audio Lines Characteristics ESD Data Integrity SIM Supply Schematic Layout Using a Gpio Pad as Input Using a Gpio Pad as OutputGeneral Purpose I/O Using the Buzzer Output GPIO7 10.3Using the Alarm Output GPIO6 11.1DAC Converter DAC and ADC sectionDescription Min Max Units Command is AT#DAC=enable,value An AT command is available to use the DAC functionEnabling DAC Low Pass Filter Example Using ADC Converter Input Voltage range AD conversion Bits Resolution11.2ADC Converter 12.1Transchip Camera CameraType Sensitivity Lux Camera Interface Connectors Camera Physical Detail & Connector Camera Socket Connector Camera Board Module Main Block Diagram for supported cameras Schematic Diagrams for supported camera Camera setting shown here are the defaults ones Example usage script for cameraTaking an reading a photo 13.2Module Finishing & Dimensions Mounting the GE863-QUAD / PY on the Application Board13.1General Lead-free Alloy Surface finishing Ni/Au for all test pads Recommended foot print for the application Debug of the GE863 in Production StencilPCB pad Design Solder paste Following is the recommended solder reflow profile 13.2.6 GE863-QUAD / PY Solder Reflow GE863-QUAD Section A-A Packing System Modules orientation on tray Moisture Sensibility Conformity Assessment Issues Safety Recommandations Revision Date Changes Document Change Log21/02/06 19/09/06