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ZOE-M8B - System Integration Manual 

UBX-17045131 - R04 

Contents

  

Page 7 of 42 

Production Information 

 

 

On receiver startup, the Super-E mode uses the acquisition engine until sufficient number of satellites 
is acquired for reliable GNSS performance, and uses the tracking engine to track the satellites. By 
default, the acquisition engine is active at least for 5 minutes after the receiver startup to read the 
ephemeris of many satellites. The tracking engine is duty-cycled adaptively according to the signal 
strength in order to provide the best balance between power consumption and navigation 
performance. 

Super-E mode offers choice of 1 Hz (default), 2 Hz, or 4 Hz operation. In addition, a slower operation 
rate with an interval of 1 – 10 s can be selected. The higher 2 Hz and 4 Hz navigation rates improve 
the navigation accuracy, but they also consume more power. The power mode can be selected with 
the configuration message UBX-CFG-PMS. Update periods longer than 1 s are set with the Extended 
Power Management configuration message UBX-CFG-PM2. 

Super-E mode has two settings to tune the receiver operation. The “performance” (default) setting 
provides the best balance for power vs. performance. The “power save” setting provides up to an 
additional 15-20% power savings at the cost of position accuracy. The setting can be selected with 
the optTarget configuration option of the Extended Power Management configuration message UBX-
CFG-PM2. 

During the tracking phase of the Super-E mode, the satellite reception is duty-cycled and it is turned 
off most of the time. The receiver reads data from the satellite transmission only occasionally. Mostly 
it just checks where the tracked satellites are at that time, and then calculates the position. With 
strong enough signal strength, the active time is 1/12 of each navigation cycle. If signal level goes too 
low, the active time can go up to 1/3 of each navigation cycle. 

Optimal efficiency of Super-E mode is achieved with a strong signal level. To ensure best efficiency, 
significant power savings, and good tracking performance, the signal strength of the strongest 
satellites should be at least -146 dBm to  -144 dBm (C/N0 value of 28 dBHz to 30 dBHz). Super-E mode 
will still work if the signal level goes lower, but efficiency will then degrade. 

Some satellites become obscured every now and then when the receiver moves. In Super-E mode, the 
receiver needs to be able to track at least 6 - 8 satellites constantly. If some of the currently used 
satellites are not in view, then the receiver can start to use some other known satellite. If too many of 
the currently known satellites are obscured, the receiver must restart the acquisition engine and stop 
power optimized tracking to read ephemeris data for the new satellites. This acquisition phase lasts 
only as long as minimally needed. 

Navigation performance improves if ephemeris of many more satellites is known beforehand, because 
the receiver can then use new satellites even if several of the previously used satellites are out of view. 

The five-minute (default) initial acquisition period on receiver startup helps to read the ephemeris of 
many satellites. Ephemeris data can be provided to the receiver also with AssistNow mechanism. If 
the ephemeris data for many satellites are known, then there is no need to read this data from the 
satellite transmission. Such preloading of data improves performance especially when the receiver is 
started in a low signal level environment (e.g. indoors). The initial acquisition period can be adjusted 
with the Extended Power Management configuration message UBX-CFG-PM2. The minimum value 
for an initial acquisition period is 0 s, which can be used if, for example, valid AssistNow Online data or 
up to one-day old AssistNow Offline data are available. Depending on the age of the aiding data and 
GNSS signal conditions, an initial acquisition period up to two or three minutes may be beneficial.  

1.2.2

 

Super-E mode power consumption 

1.2.2.1

 

Super-E states 

ZOE-M8B  defaults to the  Super-E  mode on power up. The receiver starts up in  the full-power 
acquisition state to search for satellites. The acquisition state continues until there is a valid 3D fix 
and the receiver has enough information about available satellites. For the 3D fix, the receiver needs 

Содержание ZOE-M8B GNSS SiP

Страница 1: ... small super low power u blox M8 GNSS SiP module System Integration Manual Abstract This manual provides hardware and system design instructions for the u blox ZOE M8B GNSS SiP module www u blox com UBX 17045131 R04 ...

Страница 2: ...ory compliance MAX 8 MAX M8 complies with all relevant requirements for RED 2014 53 EU The MAX 8 MAX M8 Declaration of Conformity DoC is available at www u blox com within Support Product resources Conformity Declaration This document applies to the following products Product name Type number ROM version PCN reference ZOE M8B ZOE M8B 0 10 ROM SPG 3 51 N A u blox or third parties may hold intellect...

Страница 3: ...rface 16 2 3 I O Pins 17 2 3 1 External interrupt 17 2 3 2 External LNA enable 17 2 3 3 Electromagnetic interference and I O lines 17 2 4 Real Time Clock RTC 17 2 4 1 RTC using a crystal 18 2 4 2 RTC using an external clock 18 2 4 3 Time aiding 18 2 5 RF input 18 2 5 1 Passive Antenna 19 2 5 2 Active Antenna 19 2 6 Safe Boot Mode SAFEBOOT_N 20 2 7 System Reset RESET_N 20 2 8 Pin description 21 2 9...

Страница 4: ...ing 34 4 1 Packaging shipping storage and moisture preconditioning 34 4 2 ESD handling precautions 34 4 3 Safety precautions 34 4 4 Soldering 35 4 4 1 Soldering paste 35 4 4 2 Reflow soldering 35 4 4 3 Optical inspection 35 4 4 4 Repeated reflow soldering 35 4 4 5 Wave soldering 35 4 4 6 Rework 35 4 4 7 Use of ultrasonic processes 35 5 Product testing 36 5 1 Test parameters for OEM manufacturer 36...

Страница 5: ...ZOE M8B System Integration Manual UBX 17045131 R04 Page 5 of 42 Production Information Related documents 41 Revision history 41 Contact 42 ...

Страница 6: ...ered Land Grid Array packaging technology which enables easier and more reliable soldering processes compared to a normal LGA Land Grid Array package For product features see the ZOE M8B Data Sheet 1 To determine which u blox product best meets your needs see the product selector tables on the u blox website www u blox com 1 2 Low power operation The ZOE M8B GNSS SiP is designed for use in portabl...

Страница 7: ...good tracking performance the signal strength of the strongest satellites should be at least 146 dBm to 144 dBm C N0 value of 28 dBHz to 30 dBHz Super E mode will still work if the signal level goes lower but efficiency will then degrade Some satellites become obscured every now and then when the receiver moves In Super E mode the receiver needs to be able to track at least 6 8 satellites constant...

Страница 8: ...ty of the GNSS signal If the signal is attenuated blocked or reflected the power consumption acquisition speed and positioning accuracy suffer Application design including antenna performance also contributes to the signal quality Use of assistance often helps to improve both performance and power consumption In the following examples current consumption in Super E mode is shown for open forest an...

Страница 9: ...mproves TTFF and reduces current consumption in all cases as seen in Figure 4 Figure 6 and Figure 8 Figure 2 ZOE M8B continuous mode current consumption in open environment Figure 3 ZOE M8B Super E mode current consumption in open environment Figure 4 ZOE M8B Super E mode current consumption in open environment with AssistNow Offline ...

Страница 10: ...duction Information Figure 5 ZOE M8B Super E mode current consumption in obstructed environment forest Figure 6 ZOE M8B Super E mode current consumption in obstructed environment forest with AssistNow Offline Figure 7 ZOE M8B Super E mode current consumption in urban environment ...

Страница 11: ...ZOE M8B System Integration Manual UBX 17045131 R04 Contents Page 11 of 42 Production Information Figure 8 ZOE M8B Super E mode current consumption in urban environment with AssistNow Offline ...

Страница 12: ... 1 1 2 Backup power supply V_BCKP In the case of a power failure at main supply VCC the backup domain and optional RTC oscillator are supplied by V_BCKP Providing a V_BCKP supply maintains the time RTC and the GNSS orbit data in backup RAM This ensures that any subsequent re starts after a VCC power failure will benefit from the stored data providing a faster TTFF The GNSS satellite ephemeris data...

Страница 13: ...ption to put the receiver into backup state All essential data for quick re starting of navigation can be saved either on the receiver or on the host processor side Unlike some other u blox M8 receivers the ZOE M8B GNSS SiP does not support self managed ON OFF power saving mode in which the receiver periodically puts itself into backup state when an operation interval longer than 10 s is selected ...

Страница 14: ...UBX CFG PMS UBX CFG PM2 as well as UBX CFG RATE messages For update rates from 1 Hz to 4 Hz it is recommended to use a uniform update rate for all Super E states For longer update periods up to 10 s it is recommended to set the acquisition and tracking state update rate to 1 Hz with the UBX CFG RATE message This may speed up the return to the power optimized tracking state in case the receiver nee...

Страница 15: ...SDA SPI CS_N Table 2 Communication Interfaces overview It is not possible to use the SPI interface simultaneously with the DDC or UART interface For debugging purposes it is recommended to have a second interface e g DDC available that is independent from the application and accessible via test points For each interface a dedicated pin can be defined to indicate that data is ready to be transmitte...

Страница 16: ...lar module to confirm compatibility 2 2 3 SPI interface The SPI interface can be used to provide a serial communication with a host CPU If the SPI interface is used UART and DDC are deactivated because they share the same pins To make use of the SPI interface the D_SEL pin has to be connected to GND 2 2 4 SQI interface An external SQI Serial Quad Interface Flash memory can be connected to the ZOE ...

Страница 17: ...ng them as noise into the GNSS receiver This specifically applies to unshielded lines lines where the corresponding GND layer is remote or missing entirely and lines close to the edges of the printed circuit board If for example a cellular signal radiates into an unshielded high impedance line it is possible to generate noise in the order of volts and not only distort receiver operation but also d...

Страница 18: ...mVpp can be achieved with a resistive voltage divider followed by a DC blocking capacitor in the range of 1 nF to 10 nF Also make sure the frequency versus temperature behavior of the external clock is within the recommended crystal specification shown in section A 1 2 4 3 Time aiding Time can also be sent by UBX message at every startup of the ZOE M8B GNSS SiP to enable warm starts AssistNow Auto...

Страница 19: ...against RF power and ESD The external LNA U1 must be placed close to the passive antenna to get best performance If Power Save Mode is used and the minimum current consumption has to be achieved then the external LNA should also be turned off The LNA_EN pin can be used to turn off the external LNA ESD discharge into the RF input cannot always be avoided during assembly and or field use with this a...

Страница 20: ...8 u blox M8 Receiver Description Including Protocol Specification 3 Safe Boot Mode is used in production to program the SQI Flash It is recommended to have the possibility to pull the SAFEBOOT_N pin low when the SiP starts up This can be provided using an externally connected test point or via a host CPUs digital I O port 2 7 System Reset RESET_N The ZOE M8B GNSS SiP provides a RESET_N pin to rese...

Страница 21: ...SQI_D0 I O Data line 0 to external SQI flash memory or reserved configuration pin Leave open if not used D3 SQI_CS_N I O Chip select for external SQI flash memory or configuration enable pin Leave open if not used D4 D_SEL I Interface selector See section 0 D6 GND Ground Ensure good GND connection D9 GND Ground Ensure good GND connection E1 SQI_CLK I O Clock for external SQI flash memory or config...

Страница 22: ... V_BCKP I Backup supply J1 VCC I Supply voltage Clean and stable supply needed J2 VCC I Supply voltage Clean and stable supply needed J3 GND Ground Ensure good GND connection J4 RXD SPI MOSI I Serial interface See section 0 J5 TXD SPI MISO O Serial interface See section 0 J6 RESET_N I System reset See section 2 7 J7 RTC_I I RTC Input Connect to GND if no RTC Crystal attached J8 RTC_O O RTC Output ...

Страница 23: ...ided the following differences are considered At start up the ZOE M8B defaults to Super E mode whereas ZOE M8G defaults to continuous mode Galileo operation is supported only in Continuous mode Galileo should be disabled in Super E mode Time pulse is not supported in ZOE M8B In ZOE M8B time mark is supported only in Continuous mode and in acquisition phase of Super E mode It is not supported in th...

Страница 24: ...h interference issues see the GPS Antenna Application Note 4 2 11 2 Schematic design in for ZOE M8B GNSS SiP For a minimal design with the ZOE M8B GNSS SiP the following functions and pins need to be considered Connect the power supply to VCC and V_BCKP Ensure an optimal ground connection to all ground pins of the ZOE M8B GNSS SiP Choose the required serial communication interfaces UART SPI or DDC...

Страница 25: ...ayer for the micro strip coplanar waveguide calculation If the distance between the micro strip and the adjacent GND area on the same layer does not exceed 5 times the track width of the micro strip use the Coplanar Waveguide model in AppCad to calculate the micro strip and not the micro strip model 2 13 Layout This section provides important information for designing a reliable and sensitive GNSS...

Страница 26: ...c and voltage susceptibility issues Wireless systems include components which can produce Electrostatic Discharge ESD Electrical Overstress EOS and Electro Magnetic Interference EMI CMOS devices are more sensitive to such influences because their failure mechanism is defined by the applied voltage whereas bipolar semiconductors are more susceptible to thermal overstress The following design guidel...

Страница 27: ...antennas Active Antennas C D LNA with appropriate ESD rating and maximum input power Figure 20 EOS and ESD Precautions 2 14 5 Electromagnetic interference EMI Electromagnetic interference EMI is the addition or coupling of energy which causes a spontaneous reset of the GNSS receiver or results in unstable performance In addition to EMI degradation due to self jamming see Section 2 3 3 any electron...

Страница 28: ... Make sure that absolute maximum input power level of the GNSS receiver is not exceeded See the GPS Implementation and Aiding Features in u blox wireless modules 4 2 14 6 1 Isolation between GNSS and GSM antenna In a handheld type design an isolation of approximately 20 dB can be reached with careful placement of the antennas If such isolation can t be achieved e g in the case of an integrated GSM...

Страница 29: ...fore handset antenna 2 14 6 4 Out band interference Out band interference is caused by signal frequencies that are different from the GNSS carrier see Figure 23 The main sources are wireless communication systems such as GSM CDMA HSPA Wi Fi Bluetooth etc Figure 23 Out band interference signals Measures against out band interference include maintaining a good grounding concept in the design and add...

Страница 30: ...n data when it starts up Receiving this information from the satellite broadcasts takes a long time and requires a high GNSS signal level Using a backup mode is a way to turn off the receiver while maintaining the knowledge about satellite navigation data Additionally RTC or time aiding can be used to maintain the information about GNSS time Using these methods leads to better acquisition sensitiv...

Страница 31: ...er optimized period The A GNSS assistance data also improves tracking accuracy in Super E mode because the receiver can optimize the set of satellites used in power optimized tracking Performance of the GNSS operation is improved in several aspects The TTFF can be reduced down to a couple of seconds The signal acquisition before entering the power optimized tracking is improved Thus more satellite...

Страница 32: ... automatically generates accurate predictions of satellite orbital data AssistNow Autonomous data that is usable for future GNSS position fixes The concept capitalizes on the periodic nature of GNSS satellites their position in the sky is repeated every 24 hours By capturing strategic ephemeris data at specific times of the day the receiver can predict accurate satellite ephemeris for up to six da...

Страница 33: ... buffer must be retrieved before making any adjustments to the buffering Retrieval of the buffered data may take longer that one navigation cycle E g retrieving a buffer of 300 position fixes over UART at 115200 baud takes slightly over 3 seconds This is longer than 300 108 10 115200 2 8 seconds because the messages are not transferred gap free There may be occasional gaps of up to 10 milliseconds...

Страница 34: ...static charges In addition to standard ESD safety practices the following measures should be taken into account whenever handling the receiver Unless there is a galvanic coupling between the local GND i e the work table and the PCB GND then the first point of contact when handling the PCB shall always be between the local GND and PCB GND Before mounting an antenna patch connect ground of the devic...

Страница 35: ...commended conditions for reflow process The peak temperature must not exceed 255 C The time above 245 C must not exceed 40 seconds The ZOE M8B GNSS SiP must not be soldered with a damp heat process 4 4 3 Optical inspection After soldering the SiP consider an optical inspection step to check whether The SiP is properly aligned and centered over the pads 4 4 4 Repeated reflow soldering Only single r...

Страница 36: ...nications Positioning Technology www positioningtechnology co uk Figure 25 Multi GNSS generator 5 2 1 Guidelines for sensitivity tests 1 Connect a Multi GNSS generator to the OEM product 2 Choose the power level in a way that the Golden Device would report a C No ratio of 38 40 dBHz 3 Power up the DUT Device Under Test and allow enough time for the acquisition 4 Read the C N0 value from the NMEA G...

Страница 37: ...c Protective Area ESD Electrostatic discharge Galileo European navigation system GLONASS Russian satellite system GND Ground GNSS Global Navigation Satellite System GPS Global Positioning System GSM Global System for Mobile Communications IEC International Electrotechnical Commission LGA Land Grid Array PCB Printed circuit board SBAS Satellite Based Augmentation System S LGA Soldered Land Grid Arr...

Страница 38: ...facturer data sheet for DC ESD and RF power ratings Manufacturer Order No System supported Comments TDK EPCOS B8401 B39162B8401P810 GPS GLONASS High attenuation TDK EPCOS B3913 B39162B3913U410 GPS GLONASS BeiDou For automotive application TDK EPCOS B9416 B39162B9416K610 GPS High input power TDK EPCOS B4310 B39162B4310P810 GPS GLONASS Compliant to the AEC Q200 standard TDK EPCOS B4327 B39162B4327P8...

Страница 39: ...mmend parts list for optional SQI Flash B 4 External LNA U1 ID Parameter Value 1 Gain and Noise Figure 1 575 GHz 1 1 Gain 17 dB 1 2 Noise Figure 2 dB Table 11 External LNA specifications Manufacturer Order No Comments Maxim MAX2659ELT Low noise figure up to 10 dBm RF input power JRC New Japan Radio NJG1143UA2 Low noise figure up to 15 dBm RF input power NXP BGU8006 Low noise figure very small pack...

Страница 40: ...signals 34 pF load capacitance MuRata NFA18SL307V1A45 For data signals 4 circuits in 1 package MuRata NFM18PC474R0J3 For power supply 2 A size 0603 MuRata NFM21PC474R1C3 For power supply 4 A size 0805 Table 15 Recommend parts list for feed thru capacitors B 8 Standard capacitors Name Use Type Value C4 Decoupling VCC at SQI Flash supply pin X5R 1U0 10 6 3V Table 16 Standard capacitors ...

Страница 41: ...ard IEC 60950 1 https webstore iec ch publication 4024 For regular updates to u blox documentation and to receive product change notifications register on our homepage www u blox com Revision history Revision Date Name Comments R01 12 Oct 2017 rmak Objective Specification R02 31 Jan 2018 rmak Early Production Information Updated Sections 1 2 2 2 1 2 1 2 10 3 2 2 3 3 and A 3 Added DoC statement on ...

Страница 42: ...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 mail in...

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