Telit Wireless Solutions GE863-PY, GE863-QUAD manual Output Lines Speaker, Short description

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GE863-QUAD

GE863-PY

1vv0300715 Rev. 1 - 19/09/06

8 OUTPUT LINES (Speaker)

8.1 Short description

The Telit GE863-QUAD / PY provides two audio paths in receive section. Only one of the two paths can be active at a time, selectable by AXE hardware line or by AT command.

You must keep in mind the different audio characteristics of the receive blocks when designing :

the “Ear_MT” lines EPN1 and EPP1 are the Differential Line-Out Drivers ; they can drive an external amplifier or directly a 16 Ω earpiece at –12dBFS (*) ;

the “Ear_HF” lines EPPA1_2 and EPPA2 are the Fully Differential Power Buffers ; they can directly drive a 16Ω speaker in differential (balanced) or single ended (unbalanced) operation mode .

(*)FS : acronym of Full Scale. It is equal to 0dB, the maximum Hardware Analog Receive Gain of BaseBand Chip.

The “Ear_MT” audio path should be used for handset function, while the “Ear_HF” audio path is suited for hands-free function (car kit).

Both receiver outputs are B.T.L. type (Bridged Tie Load) and the OEM circuitry shall be designed bridged to reduce the common mode noise typically generated on the ground plane and to get the maximum power output from the device; however also a single ended circuitry can be designed for particular OEM application needs.

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Contents GE863-QUAD GE863-PY Hardware User Guide Contents 10.1 10.210.3 10.413.2 12.113.1 This document is relating to the following products Overview GE863 module connections PIN-OUTPin Signal Function Internal Type Pull up Pin Signal Function Internal Type Pins Layout Hardware Commands Turning on the GE863-QUAD/PYTurning OFF the GE863-QUAD/PY Turning off of the device can be done in two waysHardware Unconditional Reboot Hardware shutdownGE863-QUAD GE863-QUAD/PY power requirements are Power Supply1Power Supply Requirements 2General Design Rules Electrical design Guidelines1.2 + 12V input Source Power Supply Design Guidelines An example of linear regulator with 5V input isBattery Source Power Supply Design Guidelines An example of switching regulator with 12V input isBattery Charge control Circuitry Design Guidelines Thermal Design Guidelines Power Supply PCB layout Guidelines Antenna GSM Antenna RequirementsGSM Antenna PCB line Guidelines GSM Antenna installation GuidelinesSerial Ports Absolute Maximum Ratings -Not Functional Parameter Min Max Level Min MaxSignals in the Uart connector on the EVK are Number Pad Number17-28-36 Ground 45-48-50-56 Clear to Send Output from the GE863-QUAD/PY that3RS232 level translation It is available on the following pins2MODEM Serial Port 2 Python Debug An example of level translation circuitry of this kind is 5V Uart level translation GE863-QUAD Audio Section Overview GM863-GPS Microphone Paths Characteristic and Requirements Echo canceller type HandsetEcho canceller type Car kit hands-free + 20dBThat means You can set GA= +20dB to use standard resistor valuesTIP environment consideration General Design Rules Other considerationsMicrophone Biasing Balanced Microphone BiasingUnbalanced Microphone Biasing GE863-QUAD Sample circuit can be Microphone BufferingBuffered Balanced Mic Gain = RR604605 = RR607606 Buffer gain is given by the formula Buffered Unbalanced Single Ended Microphone Freq . = 2π * R719* C726 2π * R711* C727 Buffer bandwidth at -3dB shall be 4KHzGE863-QUAD Output Lines Speaker Short descriptionOutput Lines Characteristics SW volume level step Number of SW volume stepsNoise Filtering Handset Earphone Design Hands-Free Earphone Low Power Design An example of internal Ear amplifier could beCar Kit Speakerphone Design Evaluation Kit for Telit Modules EVK2 Short Description2 EVK2 Audio Lines Characteristics @ 350mWData Integrity ESDSchematic SIM SupplyLayout General Purpose I/O Using a Gpio Pad as InputUsing a Gpio Pad as Output 10.3Using the Alarm Output GPIO6 Using the Buzzer Output GPIO7DAC and ADC section 11.1DAC ConverterDescription Min Max UnitsAn AT command is available to use the DAC function Command is AT#DAC=enable,valueEnabling DAC Low Pass Filter Example11.2ADC Converter Using ADC ConverterInput Voltage range AD conversion Bits Resolution Camera 12.1Transchip CameraType Sensitivity LuxCamera Interface Connectors Camera Physical Detail & Connector Camera Socket Connector Camera Board Module Main Block Diagram for supported cameras Schematic Diagrams for supported camera Taking an reading a photo Camera setting shown here are the defaults onesExample usage script for camera 13.1General 13.2Module Finishing & DimensionsMounting the GE863-QUAD / PY on the Application Board Surface finishing Ni/Au for all test pads Lead-free AlloyRecommended foot print for the application PCB pad Design Debug of the GE863 in ProductionStencil Solder paste 13.2.6 GE863-QUAD / PY Solder Reflow Following is the recommended solder reflow profileGE863-QUAD Packing System Section A-AModules orientation on tray Moisture Sensibility Conformity Assessment Issues Safety Recommandations Document Change Log Revision Date Changes21/02/06 19/09/06