Telit Wireless Solutions GE863-QUAD, GE863-PY DAC and ADC section, 11.1DAC Converter, Description

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GE863-QUAD

GE863-PY

1vv0300715 Rev. 1 - 19/09/06

11 DAC and ADC section

11.1DAC Converter

11.1.1Description

The GE863-QUAD / PY module provides a Digital to Analog Converter. The signal (named DAC_OUT) is available on BGA Ball #63 of the GE863-QUAD / PY module and on pin 17 of PL104 on EVK2 Board (CS1151).

The on board DAC is a 10 bit converter, able to generate a analogue value based a specific input in the range from 0 up to 1023. However, an external low-pass filter is necessary

	Min	Max		Units
Voltage range (filtered)	0	2,6		Volt
Range	0	1023		Steps

The precision is 10 bits so, if we consider that the maximum voltage is 2V, the integrated voltage could be calculated with the following formula:

Integrated output voltage = 2 * value / 1023

DAC_OUT line must be integrated (for example with a low band pass filter) in order to obtain an analog voltage.

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Contents GE863-QUAD GE863-PY Hardware User Guide Contents 10.2 10.110.3 10.412.1 13.113.2 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 RebootGE863-QUAD Power Supply 1Power Supply RequirementsGE863-QUAD/PY power requirements are 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 installation Guidelines Serial PortsGSM Antenna PCB line Guidelines 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 thatIt 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 + 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 Microphone Buffering Buffered Balanced MicSample circuit can be 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 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 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 ExampleUsing ADC Converter Input Voltage range AD conversion Bits Resolution11.2ADC Converter 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 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 padsRecommended 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 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