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UBX-15029985 - R08 

 

 

C1-Public 

 

www.u-blox.com

 

 

 
 

NEO-8Q / NEO-M8 

u-blox 8 / M8 GNSS modules 

Hardware integration manual 
 
 
 
 
 
 
 
 

 

 

Abstract

 

This document describes the features and specifications of u-blox NEO-8Q and NEO-M8 series 
modules. 

 

Содержание NEO-8Q

Страница 1: ...29985 R08 C1 Public www u blox com NEO 8Q NEO M8 u blox 8 M8 GNSS modules Hardware integration manual Abstract This document describes the features and specifications of u blox NEO 8Q and NEO M8 series modules ...

Страница 2: ... M Q T Declaration of Conformity DoC is available at www u blox com in Support Product resources Conformity Declaration This document applies to the following products Product name Type number ROM FLASH version PCN reference NEO M8N NEO M8N 0 11 FLASH FW SPG 3 01 UBX 20013367 NEO M8M NEO M8M 0 11 ROM SPG 3 01 UBX 21015022 NEO M8Q NEO M8Q 0 11 ROM SPG 3 01 UBX 20013367 NEO M8T NEO M8T 0 11 FLASH FW...

Страница 3: ...ernal interrupt 8 1 5 3 SAFEBOOT_N 9 1 5 4 D_SEL Interface select 9 1 5 5 TIMEPULSE TIMEPULSE1 on NEO M8T 9 1 5 6 TIMEPULSE2 9 1 5 7 LNA_EN LNA enable 9 1 6 Electromagnetic interference on I O lines 10 2 Design 11 2 1 Pin description 11 2 1 1 Pin name changes 12 2 2 Minimal design 12 2 3 Layout Footprint and paste mask 12 2 4 Antenna 13 2 4 1 Antenna design with passive antenna 13 2 4 2 Active ant...

Страница 4: ...29985 Production information Contents Page 4 of 5 C1 Public 4 2 Soldering 19 4 3 EOS ESD EMI precautions 22 4 4 Applications with cellular modules 25 Appendix 27 A Glossary 27 B Recommended parts 27 Related documents 29 Revision history 30 Contact 31 ...

Страница 5: ...battery supply is not interrupted For the NEO M8N and NEO M8J modules configuration can be saved permanently in SQI flash 1 3 Connecting power The u blox NEO 8Q and NEO M8 series modules have three power supply pins VCC V_BCKP and VDD_USB 1 3 1 VCC Main supply voltage The VCC pin provides the main supply voltage During operation the current drawn by the module can vary by some orders of magnitude ...

Страница 6: ...till runs providing a timing reference for the receiver This operating mode is called Hardware Backup Mode which enables all relevant data to be saved in the backup RAM to allow a hot or warm start later 1 3 3 VDD_USB USB interface power supply VDD_USB supplies the USB interface If the USB interface is not used the VDD_USB pin must be connected to GND For more information about correctly handling ...

Страница 7: ...Depending on the characteristics of the LDO U1 it is recommended to add a pull down resistor R11 at its output to ensure VDD_USB is not floating if the LDO U1 is disabled or the USB cable is not connected that is VBUS is not supplied USB bus powered mode is not supported Module VDD_USB LDO VDD_USB R4 USB_DP USB_DM R5 C24 C23 D2 VBUS DP DM GND USB Device Connector U1 EN R11 EN Figure 2 USB interfac...

Страница 8: ... can be enabled and configured by AT commands sent to the u blox cellular module supporting the feature For more information see the GPS Implementation and Aiding Features in u blox wireless modules 8 1 5 I O pins All I O pins make use of internal pull ups Thus there is no need to connect unused pins to VCC_IO 1 5 1 RESET_N Reset Driving RESET_N low activates a hardware reset of the system Use thi...

Страница 9: ...ture service updates and reconfiguration On the NEO M8T module a configurable TIMEPULSE2 signal can be programmed on TP2 SAFEBOOT_N Do not pull low during reset 1 5 4 D_SEL Interface select The D_SEL pin selects the available interfaces SPI cannot be used simultaneously with UART DDC If open UART and DDC are available If pulled low the SPI interface is available See the corresponding product data ...

Страница 10: ...ded high impedance line it is possible to generate noise in the order of volts and not only distort receiver operation but also damage it permanently On the other hand noise generated at the I O pins will emit from unshielded I O lines Receiver performance may be degraded when this noise is coupled into the GNSS antenna see Figure 15 To avoid interference by improperly shielded lines it is recomme...

Страница 11: ...Serial input Internal pull up resistor to VCC Leave open if not used If pin 2 low SPI MOSI USB USB_DM 5 I O USB I O line USB bidirectional communication pin Leave open if unused USB_DP 6 I O USB I O line System TIMEPULSE TIMEPULSE1 NEO M8T 3 O Timepulse signal Configurable Timepulse signal one pulse per second by default Leave open if not used SAFEBOOT_N TP2 SAFEBOOT_N NEO M8T 1 I SAFEBOOT_N SAFEB...

Страница 12: ...ign This is a minimal design for a NEO 8Q and NEO M8 series GNSS receiver Figure 4 NEO 8Q NEO M8 passive antenna design NEO M8M can support passive antenna but for optimal operation it requires an external SAW and LNA see Figure 7 2 3 Layout Footprint and paste mask Figure 5 describes the footprint of the NEO 8Q and NEO M8 series modules and provides recommendations not specifications for the past...

Страница 13: ...re with the antenna performance Passive antennas do not require a DC bias voltage and can be directly connected to the RF input pin RF_IN Sometimes they may also need a passive matching network to match the impedance to 50 Ω Use an antenna that has sufficient bandwidth to receive all GNSS constellations See the Appendix Figure 6 shows a minimal setup for a design with a good GNSS patch antenna For...

Страница 14: ...y In that case the LNA must be placed close to the passive antenna Figure 8 NEO M8N J T Q and NEO 8Q module design with passive antenna and an external LNA The LNA_EN pin LNA enable can be used to turn on and off an optional external LNA The VCC_RF output can be used to supply the LNA with a filtered supply voltage A standard GNSS LNA has enough bandwidth to amplify GPS GLONASS Galileo BeiDou sign...

Страница 15: ...enna e g 3 0 V use the filtered supply voltage available at pin VCC_RF as shown in Figure 9 For exact pin orientation see the corresponding product data sheet Active antenna design using VCC_RF pin to supply the active antenna Figure 9 Active antenna design external supply from VCC_RF If the VCC_RF voltage does not match the supply voltage of the active antenna use a filtered external supply as sh...

Страница 16: ...signal tracking Sources can include co located power devices cooling fans or thermal conduction via the PCB Consider the following questions when designing in the module Is the receiver placed away from heat sources Is the receiver placed away from air cooling sources Is the receiver shielded by a cover case to prevent the effects of air currents and rapid environmental temperature changes High te...

Страница 17: ...EO M8 series Remarks for migration Pin name Typical assignment Pin name Typical assignment 1 SAFEBOOT_N Leave open SAFEBOOT_N Leave open No difference 2 SS_N SPI slave select D_SEL Selects the interface Various functions compatible only when not using SPI for communication 3 TIMEPULSE 1 Timepulse 1 1PPS TIMEPULSE TIMEPULSE1 Timepulse1 No difference 4 EXTINT0 External interrupt pin EXTINT EXTINT0 E...

Страница 18: ... used RESERVED Leave open 17 RESERVED Leave open RESERVED Leave open No difference 18 SDA DDC data SDA DDC data SPI CS_N No difference for DDC If pin 2 low SPI chip select 19 SCL DDC clock SCL DDC clock SPI SCK No difference for DDC If pin 2 low SPI clock 20 TxD Serial port TXD UART_TX SPI MISO No difference for UART If pin 2 low SPI MISO 21 RxD Serial port RXD UART_RX SPI MOSI No difference for U...

Страница 19: ...solder joints on the connectors half vias should meet the appropriate IPC specification Reflow soldering A convection type soldering oven is highly recommended over the infrared type radiation oven Convection heated ovens allow precise control of the temperature and all parts will heat up evenly regardless of material properties thickness of components and surface color As a reference see the IPC ...

Страница 20: ...fter soldering the u blox module consider an optical inspection step to check whether The module is properly aligned and centered over the pads All pads are properly soldered No excess solder has created contacts to neighboring pads or possibly to pad stacks and vias nearby Cleaning In general cleaning the populated modules is strongly discouraged Residues underneath the modules cannot be easily r...

Страница 21: ...ring for example pins 1 and 15 and continue from left to right Rework The u blox module can be unsoldered from the baseboard using a hot air gun When using a hot air gun for unsoldering the module a maximum of one reflow cycle is allowed In general we do not recommend using a hot air gun because this is an uncontrolled process and might damage the module Attention use of a hot air gun can lead to ...

Страница 22: ...bserve strict EOS ESD EMI handling and protection measures To prevent overstress damage at the RF_IN of your receiver never exceed the maximum input power see the corresponding product data sheet Electrostatic discharge ESD Electrostatic discharge ESD is the sudden and momentary electric current that flows between two objects at different electrical potentials caused by direct contact or induced b...

Страница 23: ...s employ additional ESD protection measures Using an LNA with appropriate ESD rating can provide enhanced GNSS performance with passive antennas and increases ESD protection Most defects caused by ESD can be prevented by following strict ESD protection rules for production and handling When implementing passive antenna patches or external antenna connection points additional ESD measures can also ...

Страница 24: ...eceiver or resulting in unstable performance In addition to EMI degradation due to self jamming see section 1 5 any electronic device near the GNSS receiver can emit noise that can lead to EMI disturbances or damage The following elements are critical regarding EMI Unshielded connectors for example pin rows Weakly shielded lines on PCB for example on top or bottom layer and especially at the borde...

Страница 25: ...additional input filter is needed on the GNSS side to block the high energy emitted by the cellular transmitter Examples of these kinds of filters are the SAW Filters from Epcos B9444 or B7839 or Murata Increasing interference immunity Interference signals come from in band and out band frequency sources In band interference With in band interference the signal frequency is very close to the GNSS ...

Страница 26: ...s that are different from the GNSS carrier see Figure 16 The main sources are wireless communication systems such as cellular CDMA WCDMA Wi Fi BT etc Figure 16 Out band interference signals Measures against out band interference include maintaining a good grounding concept in the design and adding a SAW or band pass ceramic filter as recommend in section 4 into the antenna input line to the GNSS r...

Страница 27: ...ended parts Recommended parts are selected on data sheet basis only Other components may also be used Part Manufacturer Part ID Remarks Parameters to consider Diode ON Semiconductor ESD9R3 3ST5G Standoff voltage 3 3 V Low capacitance 0 5 pF ESD9L3 3ST5G Standoff voltage 3 3 V Standoff voltage Voltage for active antenna ESD9L5 0ST5G Standoff voltage 5 V Low inductance SAW TDK EPCOS B8401 B39162B840...

Страница 28: ... Array type For data signals 4 circuits in 1 package Feed through Capacitor Murata NFM18PC NFM21P 0603 2A 0805 4A Rs 0 5 Ω Resistor 10 Ω 10 min 0 250 W Rbias 560 Ω 5 R2 100 kΩ 5 R3 R4 Table 6 Recommended parts Recommended antennas Manufacturer Order no Comments Hirschmann www hirschmann car com GLONASS 9 M GPS GLONASS active Taoglas www taoglas com AA 160 301111 36 x 36 x 4 mm 3 5 V 30 mA active T...

Страница 29: ...n including Protocol Specification Public version UBX 13003221 5 GPS Antenna Application note GPS X 08014 6 GPS Compendium GPS X 02007 7 I2C bus specification Rev 6 4 April 2014 http www nxp com documents user_manual UM10204 pdf 8 GPS Implementation and Aiding Features in u blox wireless modules GSM G1 CS 09007 9 u blox M8 FW SPG3 01 Migration Guide UBX 15028330 For regular updates to u blox docum...

Страница 30: ...Intended use case for EMI in section 4 3 EOS ESD EMI precautions updated legal statement on the cover page and added Documentation feedback e mail address in contacts page R05 10 Jul 2019 jesk Clarified use of internal pull ups in section 1 5 Clarified alternative uses for the EXTINT pin in section 1 5 2 Updated parameters for the recommended inductor in appendix B R06 24 Jan 2020 rmak Updated sec...

Страница 31: ...t_ap u blox com Regional Office China Beijing Phone 86 10 68 133 545 E mail info_cn u blox com Support support_cn u blox com Regional Office China Chongqing Phone 86 23 6815 1588 E mail info_cn u blox com Support support_cn u blox com Regional Office China Shanghai Phone 86 21 6090 4832 E mail info_cn u blox com Support support_cn u blox com Regional Office China Shenzhen Phone 86 755 8627 1083 E ...

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