Telit Wireless Solutions GE863-QUAD manual 1.2 + 12V input Source Power Supply Design Guidelines

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GE863-QUAD

GE863-PY

1vv0300715 Rev. 1 - 19/09/06

An example of linear regulator with 5V input is:

4.2.1.2 + 12V input Source Power Supply Design Guidelines

•The desired output for the power supply is 3.8V, hence due to the big difference between the input source and the desired output, a linear regulator is not suited and shall not be used. A switching power supply will be preferable because of its better efficiency especially with the 2A peak current load represented by the GE863-QUAD/PY.

•When using a switching regulator, a 500kHz or more switching frequency regulator is preferable because of its smaller inductor size and its faster transient response. This allows the regulator to respond quickly to the current peaks absorption.

•For car PB battery the input voltage can rise up to 15,8V and this should be kept in mind when choosing components: all components in the power supply must withstand this voltage.

•A Bypass low ESR capacitor of adequate capacity must be provided in order to cut the current absorption peaks, a 100μF tantalum capacitor is usually suited.

•Make sure the low ESR capacitor on the power supply output (usually a tantalum one) is rated at least 10V.

•For Car applications a spike protection diode should be inserted close to the power input, in order to clean the supply from spikes.

•A protection diode should be inserted close to the power input, in order to save the GE863- QUAD/PY from power polarity inversion. This can be the same diode as for spike protection.

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Contents GE863-QUAD GE863-PY Hardware User Guide Contents 10.2 10.110.3 10.413.2 12.113.1 This document is relating to the following products Overview PIN-OUT GE863 module connectionsPin Signal Function Internal Type Pull up Pin Signal Function Internal Type Pins Layout Turning on the GE863-QUAD/PY Hardware CommandsTurning off of the device can be done in two ways Turning OFF the GE863-QUAD/PYHardware shutdown Hardware Unconditional Reboot GE863-QUAD GE863-QUAD/PY power requirements are Power Supply1Power Supply Requirements Electrical design Guidelines 2General Design RulesAn example of linear regulator with 5V input is 1.2 + 12V input Source Power Supply Design GuidelinesAn example of switching regulator with 12V input is Battery Source Power Supply Design GuidelinesBattery Charge control Circuitry Design Guidelines Thermal Design Guidelines Power Supply PCB layout Guidelines GSM Antenna Requirements AntennaGSM Antenna PCB line Guidelines GSM Antenna installation GuidelinesSerial Ports Level Min Max Absolute Maximum Ratings -Not Functional Parameter Min MaxNumber 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 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 Echo canceller type Handset Microphone Paths Characteristic and RequirementsEcho canceller type Car kit hands-free + 20dBYou can set GA= +20dB to use standard resistor values That meansTIP environment consideration Other considerations General Design RulesBalanced Microphone Biasing Microphone BiasingUnbalanced Microphone Biasing GE863-QUAD Sample circuit can be Microphone BufferingBuffered Balanced Mic Buffer gain is given by the formula Gain = RR604605 = RR607606Buffered Unbalanced Single Ended Microphone Buffer bandwidth at -3dB shall be 4KHz Freq . = 2π * R719* C726 2π * R711* C727GE863-QUAD Short description Output Lines SpeakerSW volume level step Number of SW volume steps Output Lines CharacteristicsNoise Filtering Handset Earphone Design An example of internal Ear amplifier could be Hands-Free Earphone Low Power DesignCar Kit Speakerphone Design Short Description Evaluation Kit for Telit Modules EVK2@ 350mW 2 EVK2 Audio Lines CharacteristicsESD Data IntegritySIM Supply SchematicLayout General Purpose I/O Using a Gpio Pad as InputUsing a Gpio Pad as Output Using the Buzzer Output GPIO7 10.3Using the Alarm Output GPIO611.1DAC Converter DAC and ADC sectionDescription Min Max UnitsCommand is AT#DAC=enable,value An AT command is available to use the DAC functionEnabling DAC Low Pass Filter Example11.2ADC Converter Using ADC ConverterInput Voltage range AD conversion Bits Resolution 12.1Transchip Camera 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 Lead-free Alloy Surface finishing Ni/Au for all test padsRecommended foot print for the application PCB pad Design Debug of the GE863 in ProductionStencil Solder paste Following is the recommended solder reflow profile 13.2.6 GE863-QUAD / PY Solder ReflowGE863-QUAD Section A-A Packing SystemModules orientation on tray Moisture Sensibility Conformity Assessment Issues Safety Recommandations Revision Date Changes Document Change Log21/02/06 19/09/06