SkyTraq PX1172R - System Integration and Performance; Recommended Reflow Profile; Antenna, Power, Backup, and 1 PPS Considerations

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RECOMMANDEDREFLOWPROFILE
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Thereflowprofileshownaboveshouldnotbeexceeded,sinceexcessivetemperaturesortransporttimesduring
reflowcandamagethemodule.Coolingtemperaturefallrate:max3°C/sec
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ANTENNACONSIDERATIONS
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ThePX1172RisdesignedtobeusedwithGPSL1/L2C,GLONASSL1/L2,BeidouB1I/B2I,GalileoE1/E5bmulti‐frequency
activeantenna.Antennawithgainupto40dBandnoisefigurelessthan2dBcanbeused.Itisimportanttoselecta
high‐performanceantennatoachieveoptimalRTKperformance. 
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POWERSUPPLYREQUIREMENT
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PX1172R requires a stable power supply, avoid ripple on VCC pin (<50mVpp). Power supply noise can affect the
receiver’ssensitivity.BypasscapacitorsshouldbeplacedclosetothemoduleVCCpin,withvaluesadjusteddepending
ontheamountandtypeofnoisepresentonthesupplyline.
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BACKUPSUPPLY 
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The purpose of backup supply voltagepin (V_BCKP) is tokeep the SRAM memory and theRTCpowered when the
moduleispowereddown.Thisenablesthemoduletohaveafastertime‐to‐first‐fixwhenthemoduleispoweredon
again.Thebackupcurrentdrainislessthan55μA.Innormalpoweredonstate,theinternalprocessoraccesstheSRAM
andcurrentdrainishigherinactivemode
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1PPSOUTPUT 
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A1pulsepersecondsignal(100msecHIGHduration)isgeneratedon1PPSpinwhenthereceiverhas3Dpositionfix
using4ormoresatellites.TherisingedgeofthepulseisalignedwithUTCsecond,withaccuracyofabout10nsec.It
outputsconstantLOWwhennopositionfixisavailableinitially. 