LOCOSYS Technology Inc.
20F.-13, No.79, Sec. 1, Xintai 5th Rd.,
Xizhi Dist., New Taipei City 221, Taiwan
886-2-8698-3698
886-2-8698-3699
www.locosystech.com
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LOCOSYS provides following 1pps signal output mode for customer selections
Standard GPS module will output the 1pps after the module is 3D_FIX.
Free run 1PPS output after 3D_FIX
GPS module will output the 1pps after the module is 2D_FIX.
A customize firmware also could set the 1PPS plus out as soon as power-on disregard to
3D_Fix or not.
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Layout Guideline
3.1
Layout underneath the GPS module
GPS signal is very weak signal level around -160dBm~130dBm. Any noise or harmonic will
decrease the quality of GPS. In modern GPS product, it almost includes LCD, MCU, High
Speed digital and RF system (BT, Wi-Fi, DVB-T…). In order to minimize the influence of
mentioned noise to GPS module, please customer don’t place any trace underneath the GPS
module. In other word, give GPS module a clean GND plane is very important.
GPS on a clean GND plane
3.2
Module Placement
Place the decoupling capacitors close to GPS module
Place the damping resistors close to GPS module
Do not place:
GPS module close to high-speed digital processing circuitry
GPS module close to high-current switching power circuitry
GPS module close to clock sources circuitry
