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MIA-M10Q - Integration manual

      

      

      

      

      

Figure 36: Typical 1.8 V design

B.2 Antenna supervisor designs

Figure 37

 and 

Figure 38

 show a reference design for a 2-pin and 3-pin antenna supervisor design

respectively. Here are some key features:
• VCC and V_IO are connected together to a single supply.
• Supply at V_BCKP is optional. If present, the hardware backup mode is supported. This mode

maintains the time and GNSS orbit data in the battery-backed RAM memory if the main supply
is switched off.
If there is no backup supply, the EXTINT pin can be used for time aiding and the GNSS orbit data
can be aided using AssistNow services or downloaded to the host and fed back to the receiver
at startup.

• An external SAW filter can be placed on the RF path as shown in 

Figure 37

, which allows an SAW-

LNA-SAW RF front-end circuit for improving out-of-band immunity against RF interference from
other sources. This is especially useful when MIA-M10Q is used in cellular applications.

• An active antenna can be supplied with the VCC_RF output from MIA-M10Q or from an external

supply. VCC_RF is a filtered output voltage supply, which outputs VCC - 0.1 V. In addition, the
active antenna supply can be turned on/off by the LNA_EN signal, which also controls the internal
LNA of MIA-M10Q.

• External open drain buffers and operational amplifiers are also needed depending on whether a

2-pin or 3-pin antenna supervisor design is used.

UBX-21028173 - R01

 

Appendix

Page 82 of 89

C1-Public

Содержание MIA-M10Q

Страница 1: ...ration manual Abstract This document describes the features and application of the u blox MIA M10Q module an ultra low power standard precision GNSS receiver for high performance asset tracking applications www u blox com UBX 21028173 R01 C1 Public ...

Страница 2: ...cluded in this document Copying reproduction or modification of this document or any part thereof is only permitted with the express written permission of u blox Disclosure to third parties is permitted for clearly public documents only The information contained herein is provided as is and u blox assumes no liability for its use No warranty either express or implied is given including but not limi...

Страница 3: ...g receiver reset 33 2 6 Security 34 2 6 1 Configuration locking 34 2 7 Power management 34 2 7 1 Continuous mode 34 2 7 2 Power save mode 35 2 7 3 Backup modes 41 2 8 Time 41 2 8 1 Receiver local time 41 2 8 2 GNSS time bases 42 2 8 3 Navigation epochs 43 2 8 4 iTow timestamps 43 2 8 5 Time validity 44 2 8 6 UTC representation 44 2 8 7 Leap seconds 45 2 8 8 Date ambiguity 45 2 9 Time mark 46 2 10 T...

Страница 4: ...y design examples 64 3 2 Real time clock 65 3 2 1 RTC using a crystal oscillator 65 3 2 2 RTC using an external clock 66 3 2 3 RTC not used 66 3 3 RF interference 67 3 3 1 In band interference 67 3 3 2 Out of band interference 68 3 3 3 Spectrum analyzer 68 3 4 RF front end 69 3 4 1 Internal LNA modes 69 3 4 2 Out of band blocking immunity 70 3 4 3 Out of band rejection 71 3 4 4 Antenna power suppl...

Страница 5: ...l components 85 C 1 Standard capacitors 85 C 2 Standard resistors 85 C 3 Inductors 85 C 4 Operational amplifier 86 C 5 Open drain buffers 86 C 6 Antenna supervisor switch transistors 86 C 7 RTC crystal Y2 86 Related documents 87 Revision history 88 UBX 21028173 R01 Contents Page 5 of 89 C1 Public ...

Страница 6: ...rs great RF sensitivity and can improve the dynamic position accuracy in non line of sight scenarios The extremely low power consumption of 25 mW in continuous tracking mode allows great power autonomy for all battery operated devices such as asset trackers without compromising on GNSS performance For maximum sensitivity in passive antenna designs MIA M10Q integrates an LNA followed by a SAW filter...

Страница 7: ... M10Q pin assignment Pin no Name PIO no I O Description Remarks A1 GND Connect to GND A2 GND Connect to GND A3 GND Connect to GND A4 RTC_I I RTC input Leave open if not used See Real time clock for more information A5 RTC_O O RTC output Connect to GND if not used A6 EXTINT 5 I O External interrupt See EXTINT for more information 1 A7 TIMEPULSE 4 O Time pulse signal See section TIMEPULSE for more i...

Страница 8: ...ise leave it open The SAFEBOOT_N pin is internally connected to TIMEPULSE pin through a 1 kΩ series resistor C9 GND Connect to GND D1 SDA 2 I O I2C data If not used leave open Alternative functions 1 D2 Reserved Connect to E2 D9 Reserved Leave open E1 SCL 3 I I2C clock If not used leave open Alternative functions 1 E2 Reserved Connect to D2 E3 GND Connect to GND E4 GND Connect to GND E7 Reserved L...

Страница 9: ...formation J1 Reserved Leave open J2 Reserved Leave open J3 Reserved Leave open J4 V_IO I IO voltage supply See V_IO for more information J5 V_BCKP I Backup voltage supply Leave open if no external backup supply See V_BCKP for more information J6 VIO_SEL I Voltage selector for V_IO supply Connect to GND for 1 8 V supply or leave open for 3 3 V supply J7 Reserved Leave open J8 GND Connect to GND J9 ...

Страница 10: ...rs Users must adopt the configuration interface described in this document The configuration interface settings are stored in a database consisting of separate configuration items An item is made up of a pair consisting of a key ID and a value Related items are grouped together and identified under a common group name CFG GROUP a convention used in u center 2 and within this document Within u center 2...

Страница 11: ...lling CFG HW RF_LNA_MODE at RAM layer using the UBX CFG VALGET message 6 The OTP memory configuration is completed 2 1 1 3 GNSS signal configuration MIA M10Q supports concurrent reception of four major GNSS constellations using the GPS L1C A Galileo E1 BeiDou B1C and GLONASS L1OF signals BeiDou B1I signal is also supported but cannot be used simultaneously with BeiDou B1C or GLONASS L1OF signals The...

Страница 12: ...ation epoch is calculated However this second option demands fewer resources and is the correct procedure when the navigation rate is changed Setting a navigation rate value higher than one 1 is only needed when it is required that the raw measurement data is output at a higher rate than the navigation data The output rate for each message is defined in the CFG MSGOUT configuration group If the outp...

Страница 13: ...T_CFG_RECOVER Enable auto recovery in the event of a short circuit To use this feature enable short circuit detection and CFG HW ANT_CFG_PWRDOWN CFG HW ANT_SUP_SWITCH_PIN PIO number of the pin used for switching antenna supply PIO5 is recommended if available This pin can be used as an LNA_EN signal to control an external LNA especially if software standby mode or power save mode on off PSMOO opera...

Страница 14: ...6 Dynamic platform models Platform Max altitude m Max horizontal velocity m s Max vertical velocity m s Sanity check type Max position deviation Portable 12000 310 50 Altitude and velocity Medium Stationary 9000 10 6 Altitude and velocity Small Pedestrian 9000 30 20 Altitude and velocity Small Automotive 6000 100 15 Altitude and velocity Medium At sea 500 25 5 Altitude and velocity Medium Airborne...

Страница 15: ...types of fixes for example 2D 3D Where a fix has been achieved the fix is checked to determine whether it is valid or not A fix is only valid if it passes the navigation output filters as defined in CFG NAVSPG OUTFIL In particular both PDOP and accuracy values must be below the respective limits Important Users are recommended to check the gnssFixOK flag in the UBX NAV PVT or the NMEA valid flag Fixes not...

Страница 16: ...he noise in the position output when the velocity is below a predefined Static Hold Threshold level This reduces the position wander caused by environmental factors such as multi path and improves position accuracy especially in stationary applications By default static hold mode is disabled The CFG MOT GNSSSPEED_THRS configuration item defines the static hold speed threshold If the speed drops below...

Страница 17: ... accuracy for example with bad signals or if the absolute speed value is very low under 0 1 m s then the course over ground value becomes inaccurate too In this case the course over ground value is frozen that is the previous value is kept and its accuracy degrades over time These frozen values will not be output in the NMEA messages NMEA RMC and NMEA VTG unless the NMEA protocol is explicitly con...

Страница 18: ... configured value These modes can be selected using CFG NAVSPG SIGATTCOMP In the case of the configured mode the user should input the maximum C N0 observed in a clear sky environment excluding any outliers or unusually high values Choose the configured value carefully as it can have a large impact on the receiver performance 2 2 Augmentation systems 2 2 1 SBAS MIA M10Q is capable of receiving multip...

Страница 19: ... Primary 24 Mixed fast long term corrections Primary 25 Long term corrections Primary 26 Ionosphere delays Primary Table 9 Supported SBAS messages Each satellite serves a specific region and its correction signal is only useful within that region Planning is crucial to determine the best possible configuration especially in areas where signals from different SBAS systems can be received Example 1 SBA...

Страница 20: ...on QZSS SLAS visit qzss go jp en Multiple QZSS SLAS signals can be received simultaneously When receiving QZSS SLAS correction data MIA M10Q will autonomously select the best QZSS satellite The selection strategy is determined by the quality of the QZSS L1S signals the receiver configuration test mode allowed or not and the location of the receiver with respect to the QZSS SLAS coverage area When o...

Страница 21: ...be used as a host interface which supports a configurable baud rate and protocol selection Neither handshaking signals nor hardware flow control signals are supported The UART baud rate can be configured for selected speeds different rates for transmission and reception are not supported The UART RX interface will be disabled when more than 100 frame errors are detected during a one second period This...

Страница 22: ...ds to be Most u blox receivers are configured by default with the same 7 bit address value 0x42 To poll or set the I2C slave address use the CFG I2C ADDRESS configuration item see the u blox M10 interface description 3 The CFG I2C ADDRESS configuration item is an 8 bit value containing the I2C slave address in the 7 most significant bits plus a 0 as the least significant bit Thus the default address be...

Страница 23: ...gic low for write access are clocked onto the bus by the master transmitter The receiver answers with an acknowledge logic low to indicate that it recognizes the address Next the 8 bit address of the register to be read must be written to the bus 0xFD for u blox receivers Following the receiver s acknowledgment the master again triggers a start condition and writes the device address but this time...

Страница 24: ...m If the master does not read data from the receiver for a certain timeout the receiver assumes that the communication is broken and stops the data stream preventing an overflow of the output buffer This timeout is 1 5 seconds by default However it can be extended by setting the CFG I2C EXTENDEDTIMEOUT configuration item to true see the MIA M10Q interface description 3 By disabling the timeout the re...

Страница 25: ...2C interface with the CFG I2C ENABLED configuration key if I2C pins are used for antenna supervisor functions 2 3 3 1 RESET_N MIA M10Q provides a RESET_N pin to reset the receiver The RESET_N pin is an input only pin with an internal pull up resistor to V_IO and should be left open for normal operation Driving RESET_N low for at least 1 ms will trigger a reset of the receiver The RESET_N complies w...

Страница 26: ...ate that the buffer has bytes to be transmitted The host application can wait on the signal instead of polling the interface The TX ready signal is enabled and assigned to a selected pin with CFG TXREADY configuration items The polarity of the signal active low or active high and the threshold for amount of bytes in the buffer must also be configured When the number of bytes in the buffer reaches the t...

Страница 27: ...polling the UBX MON RF message or checking the NMEA notice messages If an antenna is connected the initial state after power up is Active Antenna OK in the UBX MON RF message Features Three pin Two pin Short detection Yes Yes Open detection Yes No External components Discrete and IC Discrete and IC Number of PIOs needed Three Two Table 14 Antenna supervisor overview 2 4 1 1 Three pin antenna super...

Страница 28: ...tch to control the antenna supply U6 Comparator op amp U7 U8 Open drain buffers to shift voltage levels R7 Passive pull up to control T1 R8 Current limiter in the event of a short circuit R5 Defines the threshold of the comparator R6 Defines the threshold of the comparator Table 15 Components in antenna supervisor The threshold voltage V_REF of the comparator is defined by R5 and R6 It can be calculat...

Страница 29: ...ean as any noise could directly couple into the RF part of the GNSS receiver which will affect the overall GNSS performance Refer to Reference designs for antenna supervisor examples and the required configuration Figure 11 presents the required two pin antenna supervisor circuit and subsequent sections describe how to enable and monitor each feature Figure 11 MIA M10Q two pin antenna supervisor Tab...

Страница 30: ... Antenna power status ON ANT_OFF_N active low to disable an external antenna Therefore the pin is pulled high to enable an external antenna ANT_SHORT_N active low to report a short circuit The pin is default high PIO pull up enabled Startup message at power up if the configuration is stored GNTXT 01 01 02 ANTSUPERV AC SD 37 GNTXT 01 01 02 ANTSTATUS INIT 3B GNTXT 01 01 02 ANTSTATUS OK 25 ANTSUPERV A...

Страница 31: ...ircuit is detected ANT_SHORT_N pulled low GNTXT 01 01 02 ANTSTATUS SHORT 73 UBX MON RF Antenna status SHORT Antenna power status OFF automatic power down is enabled ANT_OFF_N low external antenna disabled After a timeout period of 60 seconds the receiver will retest the short circuit condition by enabling the antenna i e pulling ANT_OFF_N high If a short is not present the receiver will report ant...

Страница 32: ...nfigured OFF GNSS OFF or a short is detected and CFG HW ANT_PWRDOWN is enabled Note that this status also applies when GNSS is restarted via CFG RST or implicitly via CFG GNSS when GNSS selection is reconfigured or when GNSS is stopped in software standby mode and the off state of the power save mode on off PSMOO ON GNSS ON and no short open is detected from the antenna input Similarly when there is a...

Страница 33: ...me position and coarse satellite position data Almanac In this mode the receiver after power up normally needs to download ephemeris before it can calculate position and velocity data As the ephemeris data usually is outdated after 4 hours the receiver will typically start with a warm start if it has been powered down for more than 4 hours In this scenario several augmentations are possible See Mu...

Страница 34: ...g The receiver configuration can be locked so that further changes are no longer possible The configuration can be locked by setting the configuration item CFG SEC CFG_LOCK to true This item can be set in the same way as all other configuration items on various layers If the configuration lock is set on any non volatile layer i e flash BBR or OTP the operation is not reversible and cannot be undone To t...

Страница 35: ...n cyclic tracking the receiver does not shut down completely between fixes but uses low power tracking instead Some power save mode states clear the RAM memory Store receiver configuration in BBR to maintain the settings GPS GLONASS BeiDou B1I Galileo and QZSS signals are supported in power save mode BeiDou B1C signal is not supported The receiver is unable to download or process any SBAS data in po...

Страница 36: ...small number of extremely bad signals e g no sky view it will transition to the Inactive for search state after the timeout configured in MAXACQTIME User configurable mechanisms MINACQTIME is the minimum time that the receiver will spend in the Acquisition state MAXACQTIME is the maximum time that the receiver will spend in the Acquisition state DONOTENTEROFF forces the receiver to stay awake and in...

Страница 37: ...fter the configured search period minus a start up margin Once the ONTIME is over the POT state is entered Setting the ONTIME to zero causes the receiver to enter the POT state as soon as possible In the POT state the receiver continues to output position fixes according to the CFG RATE If the signal becomes weak or is lost during the POT state the Tracking state is entered Once the signal is good a...

Страница 38: ...eiver will therefore always be in the Acquisition or the Tracking state In PSMCT the receiver can in addition be in the POT state When EXTINT is set low the receiver will continue with its configured behavior Enabling EXTINTBACKUP forces the receiver to enter Inactive states for as long as the EXTINT pin is held low until the next wakeup event Any wakeup event can wake up the receiver even if the E...

Страница 39: ...eriod For short update periods in the range of a few seconds cyclic tracking should be configured For long update periods in the range of minutes or longer only use on off operation See section On Off mode and Cyclic tracking for more information on the two modes of operation POSUPDATEPERIOD ACQPERIOD The update period POSUPDATEPERIOD specifies the time between successive position fixes If no position ...

Страница 40: ...Tracking state Take into account that enabling WAITTIMEFIX will delay the transition from the Acquisition state to the Tracking state by at least two extra seconds The quality of the position fixes can also be configured by setting the limits in the CFG NAVSPG group Setting harder limits in CFG NAVSPG will typically prolong the time in the Acquisition state When externally controlled it is therefore...

Страница 41: ...XM PMREQ The V_IO and VCC must be supplied however VCC supply is internally disabled to save power The V_IO supply maintains the BBR RTC and PIOs Entering the software standby mode clears the RAM memory including the receiver configuration To maintain the configuration store it on both RAM and battery backed RAM BBR layers The software standby mode can be set for a specific duration or until the rece...

Страница 42: ...pins and output via the TIMEPULSE pin and the parameters reported in corresponding messages The CFG TP TIMEGRID_TP configuration item allows the user to choose between any of the supported GNSS GPS GLONASS BeiDou etc time bases and UTC Also the CFG NAVSPG UTCSTANDARD configuration item allows the user to select which variant of UTC the receiver should use This includes an automatic option which caus...

Страница 43: ...S time base for its GNSS system time conversion to GPS time requires no work at all but conversion to UTC requires knowledge of the number of leap seconds since GPS time started and other minor correction terms The relevant GPS to UTC conversion parameters are transmitted periodically every 12 5 minutes by GPS satellites but can also be supplied to the receiver via the UBX MGA GPS UTC aiding messa...

Страница 44: ... set the time validity can be confirmed by using an additional independent source meaning that the probability of the time to be correct is very high Note that information about time validity confirmation is only available if the confirmedAvai bit in the UBX NAV PVT message is set validDate means that the receiver has knowledge of the current date However it must be noted that this date might be wro...

Страница 45: ...longer appears directly overhead at 0 longitude at midday Occasionally a leap second is announced to bring UTC back into close alignment with the mean solar time Usually this means adding an extra second to the last minute of the year but this can also happen on 30th June When this happens UTC clocks are expected to go from 23 59 59 to 23 59 60 and only then on to 00 00 00 It is also possible to h...

Страница 46: ...OVER configuration item The following example illustrates how this works Assume that the reference rollover week number set in the firmware at compile time is 2148 which corresponds to a week in calendar year 2021 but is transmitted by the satellites as 100 In this case if the receiver sees transmissions containing week numbers in the range of 100 1023 they are interpreted as week numbers 2148 3071 ...

Страница 47: ...feature providing clock pulses with configurable duration and frequency The time pulse function can be configured using the CFG TP configuration group The UBX TIM TP message provides time information for the next pulse and the time source UBX 21028173 R01 2 Receiver functionality Page 47 of 89 C1 Public ...

Страница 48: ...applications it is recommended to calibrate the antenna cable delay against a reference timing source To get the best timing accuracy with the antenna a fixed and accurate position is needed If relative time accuracy between multiple receivers is required do not mix receivers of different product families If this is required the receivers must be calibrated accordingly by setting cable delay and use...

Страница 49: ...s set to use another setting in locked mode pulse length ratio Length or duty cycle of the generated pulse specifies either time or ratio for the pulse to be on off pulse length ratio lock Length or duty cycle of the generated pulse for locked mode In use as soon as the receiver has calculated a valid time from a received signal Only used if the corresponding item is set to use another setting in lo...

Страница 50: ...formance of the receiver restart Estimate of GNSS time can be maintained by a real time clock or it can be provided to the receiver by the host Estimate of the clock drift of the receiver local oscillator or an external reference frequency can also be provided to improve the startup performance 2 11 1 Real time clock The receiver contains a real time clock RTC The RTC section is located in the bac...

Страница 51: ...e accurate frequency from satellite transmissions A stable external reference frequency can be used to speed up receiver testing in production test setup The host system may also be able to provide the reference frequency to improve the cold start speed 2 11 4 Clock drift assistance Estimate of the clock drift of the local oscillator can also be fetched from the receiver using the UBX NAV CLOCK me...

Страница 52: ...in one dimension for PL It is not specified as a horizontal 2D or 3D value The protection level values UBX NAV PL plPos1 2 3 are confidence intervals around the reported position for example UBX NAV PVT or UBX NAV HPPOSLLH The target misleading information risk is provided in exponential notation UBX NAV PL tmirCoeff and UBX NAV PL tmirExp for example UBX NAV PL tmirCoeff 5 and UBX NAV PL tmirExp 0 re...

Страница 53: ...these cases must be checked Only if the PL is set to valid UBX NAV PL plPosValid the PL values UBX NAV PL plPos1 2 3 can be used and are reliable with respect to the target misleading information risk 2 13 Multiple GNSS assistance MGA The u blox AssistNow services provide a proprietary implementation of an A GNSS protocol compatible with u blox GNSS receivers The MGA services consist of AssistNow ...

Страница 54: ...k to the receiver when it has been restarted See the description of the UBX MGA DBD messages in the MIA M10Q interface description 3 for more information 2 13 3 AssistNow offline AssistNow Offline is a feature that combines special firmware in u blox receivers and a proprietary service run by u blox It is targeted at receivers that only have occasional internet access and so cannot use AssistNow Online...

Страница 55: ...ontain a standard HTTP query string in the request URL The query string consists of a set of key value parameters in the following form key value key value key value The following rules apply The order of keys is not important Keys and values are case sensitive Keys and values must be separated by an equals character Key value pairs must be separated by semicolons If a value contains a list each i...

Страница 56: ...ails can be found in the MIA M10Q interface description 3 Where circumstances prevent providing all three of these pieces of data providing some is likely to be better than none at all as this helps to lower the TTFF 2 13 3 3 Host based AssistNow Offline Host based AssistNow Offline involves AssistNow Offline data being stored until it is needed by the host system in whatever memory it has available The...

Страница 57: ...underlying broadcast ephemeris was intended for This makes downloading new ephemeris or aiding data for the first fix unnecessary for subsequent startups of the receiver The AssistNow Autonomous feature is disabled by default It can be enabled using the CFG ANA USE_ANA configuration item 2 13 4 1 Concept The figure below illustrates the AssistNow Autonomous concept in a graphical way Note that the figu...

Страница 58: ... information only for approximately 30 minutes This is not long enough to extend it in a usable way Orbit information of each GLONASS satellite must be collected at least for four hours to generate data Flash memory is not available in MIA M10Q 2 13 4 2 Interface Several UBX protocol messages provide interfaces to the AssistNow Autonomous feature The CFG ANA USE_ANA item is used to enable or disab...

Страница 59: ...hase of the satellite and Earth and the age of the data errors add up over time AssistNow Autonomous will typically extend a broadcast ephemeris from three up to six days The CFG ANA ORBMAXERR item allows changing this threshold by setting the maximum acceptable modeled orbit error in meters Note that this number does not reflect the true orbit error introduced by extending the ephemeris It is a st...

Страница 60: ...power off state The power down will be delayed until all calculations are done AssistNow Autonomous should be enabled if the system has sporadic access to the AssistNow Offline service In this case the receiver will intelligently choose the more reliable orbit predictions for each satellite This way the autonomous prediction can provide performance improvements if the offline data becomes old or gets o...

Страница 61: ... batched data is lost when the feature is disabled Batched fixes are always retrieved starting with the oldest fix in the buffer and progressing towards newer ones There is no way to skip certain fixes during retrieval When a UBX LOG RETRIEVEBATCH message is sent the receiver transmits all batched fixes It is recommended to send a retrieval request with sendMonFirst set This way the receiver will send ...

Страница 62: ...d format and use satellites only from a limited set of GNSS constellations With the default settings these messages contain measurement data only for a small number of satellites The raw measurement messages are enabled with the configuration keys in the CFG MSGOUT configuration group For example setting the configuration key CFG MSGOUT UBX_RXM_MEAS50_UART1 to value 1 with UBX CFG VALSET message enab...

Страница 63: ...nd consequently is interrupted if VCC supply is removed 3 1 2 V_IO V_IO supplies all the digital IOs clock and the backup domain The current drawn at V_IO depends on the activity and loading of the PIOs and the main oscillator A power interruption at V_IO will erase the battery backed RAM BBR unless there is an external supply connected to V_BCKP V_IO allows two voltage ranges 1 8 V or 3 3 V opera...

Страница 64: ...p mode and Figure 22 for designs without backup supply VIO_SEL is grounded Note that the voltage output at VCC_RF VCC 0 1 V Note that the maximum supply tolerance is 1 8 V 2 To enter hardware backup mode set the receiver to software standby mode with the UBX RXM PMREQ message before switching off V_IO and VCC 3 1 8 1 8 3 3 VCC and V_IO are supplied independently V_IO is supplied with an accurate 1 ...

Страница 65: ... kHz clock signal to the RTC input or by sending time aiding at every startup The ON OFF operation PSMOO and the software standby mode with a defined off period both require an RTC For other purposes time aiding can be used 3 2 1 RTC using a crystal oscillator MIA M10Q supports an external RTC crystal The RTC crystal is connected between RTC_I and RTC_O as shown in Figure 25 Adding external load cap...

Страница 66: ...TC_I pin form an RC low pass filter The cut off frequency of the RC filter is given by fc 1 2πRC and must be above the clock frequency with some margin This limits the maximum value for the voltage divider resistors For an input capacitance of the order of 10 pF the maximum resistance of the voltage divider resistors is in the order of a couple of hundred kΩ Refer to MIA M10Q data sheet 1 for the RTC...

Страница 67: ...erference The received GNSS signal power at the antenna is very low compared to other wireless communication signals The nominal 130 dBm received GNSS signal strength is below the thermal noise floor making a GNSS receiver susceptible to interference from nearby RF sources of any kind As an example cellular applications emit signals with power levels of approximately 30 dBm while the GNSS signal is...

Страница 68: ...e easily analyzed with this graphical tool The vertical axis compares the amplitude difference in dB for each frequency A good spectrum shape is characterized by an even noise floor along with the GNSS band For example if any unwanted spur stands out the vertical axis gives a rough approximation of the power level in dB compared to the noise floor Next to the chart the center frequency span and resol...

Страница 69: ...rference The MIA M10Q RF front end is designed for the highest sensitivity The integrated RF circuit is matched to 50 Ω and includes a built in DC block an LTE Band 13 notch filter an LNA and an SAW filter Refer to the Block diagram for an overview of the RF front end The MIA M10Q offers the best GNSS performance for designs with low or moderate RF interference levels For designs with other radio sys...

Страница 70: ...ensitivity or cause a complete loss of signal reception The severity of the interference depends on the repetition rate frequency signal level modulation and bandwidth of the signal Figure 29 shows a typical out of band immunity level for an unprotected MIA M10Q RF input The internal LNA is in low gain mode default The measurement is done at room temperature using a test signal with 64QAM modulati...

Страница 71: ...ission power and the isolation between the antennas Practical values for antenna isolation can range from 15 20 dB down to 6 10 dB for very small devices RF interference may also couple from external sources such as nearby mobile devices or base stations A simplified test board can be used to estimate the isolation between two antennas The size of the board and the placement of the antennas must ma...

Страница 72: ...impedance above 500 Ω at GNSS L1 frequencies creating an impedance mismatch with respect to the 50 Ω RF signal line This minimizes the effect of the feed point on the RF signal line and isolates the antenna supply from the RF signal line at GNSS frequencies Both R8 and L3 must have sufficient current and power rating to withstand the short circuit current Example component values for the antenna supp...

Страница 73: ...reference to the host ground by increasing the number of GND vias The GND vias will improve the GND reference between all the layers and the pads will serve as thermal relief Any stubs at the ground planes must be avoided or ended with a via to the reference ground Otherwise they could pick up and propagate interference Figure 31 GND stub ended with a via highlighted in red For the RF signal line ...

Страница 74: ...ture sensitive components inside the module like TCXOs and crystals are sensitive to sudden changes in ambient temperature which can adversely impact satellite signal tracking Sources can include co located power devices cooling fans or thermal conduction via the PCB The GND planes can conduct heat to other elements but they can act as heat dissipators as well Increasing the number of GND vias hel...

Страница 75: ...nded stencil thickness is 100 µm These are only recommendations and not specifications The exact geometry distances stencil thicknesses and solder paste volumes must be adapted to the customer s specific production processes for example soldering UBX 21028173 R01 3 Hardware integration Page 75 of 89 C1 Public ...

Страница 76: ...for example patch antenna 10 pF coax cable 50 80 pF m or soldering iron To prevent electrostatic discharge through the RF input do not touch any exposed antenna area If there is any risk that such exposed antenna area is touched in a non ESD protected work area implement proper ESD protection measures in the design When soldering RF connectors and patch antennas to the receiver s RF pin make sure ...

Страница 77: ...D 020 standard When populating the modules make sure that the pick and place machine is aligned to the copper pins of the module and not to the module edge Soldering paste Use of no clean soldering paste is highly recommended as it does not require cleaning after the soldering process The paste mask geometry for applying soldering paste should meet the recommendations given in the Layout section R...

Страница 78: ... and surface mount technology SMT devices require wave soldering to solder the THT components Only a single wave soldering process is encouraged for boards populated with modules Rework Not recommended Use of ultrasonic processes Some components on the module are sensitive to ultrasonic waves Use of any ultrasonic processes cleaning welding etc may cause damage to the GNSS receiver u blox offers no...

Страница 79: ...tion concept New configuration scheme using UBX CFG VALSET and UBX CFG VALGET messages Code change Navigation update rate Navigation update rate up to 18 Hz for single GNSS 10 Hz for 3 GNSS and 5 Hz for 4 GNSS constellations Code change optional Super S New feature Improves performance under weak signal conditions Enabled by default in current firmware Power save mode PSM PSM configuration options ha...

Страница 80: ...visor design cases Designs with 1 8 V main supply or with independent supply for VCC and V_IO must fulfill certain requirements when transitioning to hardware backup mode Refer to Supply design examples for more details B 1 Typical design Here are some key features for a MIA M10Q typical design VCC and V_IO are connected together to a single supply In designs with 3 3 V supply the VIO_SEL pin must ...

Страница 81: ... of band immunity against RF interference from other sources UART and I2C communication interfaces are available For an absolute minimum design using UART other PIOs RESET_N EXTINT TIMEPULSE SDA SCL SAFEBOOT_N can be left open Figure 35 Typical 3 3 V design UBX 21028173 R01 Appendix Page 81 of 89 C1 Public ...

Страница 82: ...wnloaded to the host and fed back to the receiver at startup An external SAW filter can be placed on the RF path as shown in Figure 37 which allows an SAW LNA SAW RF front end circuit for improving out of band immunity against RF interference from other sources This is especially useful when MIA M10Q is used in cellular applications An active antenna can be supplied with the VCC_RF output from MIA ...

Страница 83: ...ART1 ENABLED or TIMEPULSE CFG TP TP1_ENA when the pins are used for antenna supervisor functions Figure 37 2 pin antenna supervisor design The 2 pin antenna supervisor configuration required for the Figure 37 reference design is listed in Table 34 Configuration key Value CFG HW ANT_CFG_VOLTCTRL 1 true default no configuration required CFG HW ANT_SUP_SWITCH_PIN 7 default no configuration required CFG H...

Страница 84: ...esign is listed in Table 35 Configuration key Value CFG I2C ENABLED 0 false CFG HW ANT_CFG_VOLTCTRL 1 true default no configuration required CFG HW ANT_SUP_SWITCH_PIN 7 default no configuration required CFG HW ANT_CFG_SHORTDET 1 true CFG HW ANT_CFG_SHORTDET_POL 0 false CFG HW ANT_SUP_SHORT_PIN 3 CFG HW ANT_CFG_OPENDET 1 true CFG HW ANT_CFG_OPENDET_POL 1 true default no configuration required CFG HW AN...

Страница 85: ...acitor 10 nF 10 16 V X7R C18 DC block 47 pF 5 25 V C0G Table 36 Standard capacitors C 2 Standard resistors Table 37 presents the recommended resistor values for MIA M10Q Name Use Type Value R5 Antenna supervisor voltage divider 560 Ω 5 0 1 W R6 Antenna supervisor voltage divider 100 kΩ 5 0 1 W R7 Pull up resistor at antenna supervisor transistor 100 kΩ 5 0 1 W R8 Antenna supervisor current limiter...

Страница 86: ...witch transistors Name Manufacturer Order no Comments T1 T2 Vishay Si1016X T1 GE3 p channel n channel MOSFET Table 41 Recommended parts list for the antenna supervisor switch transistors C 7 RTC crystal Y2 Parameter Value Frequency specifications Oscillation mode Fundamental mode Nominal frequency at 25 C 32 768 kHz Frequency calibration tolerance at 25 C 100 ppm Electrical specifications Load capac...

Страница 87: ...X 22001426 3 u blox M10 SPG 5 10 Interface description UBX 21035062 4 u blox Packaging information reference UBX 14001652 For regular updates to u blox documentation and to receive product change notifications please register on our homepage https www u blox com UBX 21028173 R01 Related documents Page 87 of 89 C1 Public ...

Страница 88: ...egration manual Revision history Revision Date Name Comments R01 12 Aug 2022 oola imar riku Initial release Product status is available in the data sheet 1 UBX 21028173 R01 Revision history Page 88 of 89 C1 Public ...

Страница 89: ...MIA M10Q Integration manual Contact For further support and contact information visit us at www u blox com support UBX 21028173 R01 Page 89 of 89 C1 Public ...

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