L76 Hardware Design GNSS Module Series Rev. L76_Hardware_Design_V1.1 Date: 2013-02-25 www.quectel.com GNSS Module L76 Hardware Design Our aim is to provide customers with timely and comprehensive service. For any assistance, please contact our company headquarter: Quectel Wireless Solutions Co., Ltd. Room 501, Building 13, No.99, Tianzhou Road, Shanghai, China, 200233 Tel: +86 21 5108 6236 Mail: info@quectel.com Or our local office, for more information, please visit: l e t l c a i e t u n Q fide n o C http://www.quectel.com/quectel_sales_office.html For technical support, to report documentation errors, please visit: http://www.quectel.com/tecsupport.aspx GENERAL NOTES QUECTEL OFFERS THIS INFORMATION AS A SERVICE TO ITS CUSTOMERS. THE INFORMATION PROVIDED IS BASED UPON CUSTOMERS' REQUIREMENTS. QUECTEL MAKES EVERY EFFORT TO ENSURE THE QUALITY OF THE INFORMATION IT MAKES AVAILABLE. 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L76_Hardware_Design Confidential / Released 1 / 45 GNSS Module L76 Hardware Design About the document History Revision V1.0 V1.1 l e t l c a i e t u n Q fide n o C Date Author Description 2013-02-08 Ray XU Initial 2013-03-21 L76_Hardware_Design Ray XU 1. 2. 3. 4. Delete PMTK 291 command. Changed R3 to 100R in Figure 17. Updated chapter 2.4. Changed typical voltage of V_BCKP to 3.3V. Confidential / Released 2 / 45 GNSS Module L76 Hardware Design Contents About the document ................................................................................................................................... 2 Contents ....................................................................................................................................................... 3 Table Index ................................................................................................................................................... 5 Figure Index ................................................................................................................................................. 6 1 Introduction .......................................................................................................................................... 7 2 Product Concept .................................................................................................................................. 8 2.1. General Description................................................................................................................... 8 2.2. Key Features ............................................................................................................................. 9 2.3. Block Diagram ......................................................................................................................... 10 2.4. Evaluation Board ..................................................................................................................... 10 2.5. The Module Supports Protocols .............................................................................................. 11 3 Application.......................................................................................................................................... 12 3.1. Pin Assignment........................................................................................................................ 12 3.2. Pin Definition ........................................................................................................................... 12 3.3. Power Supply .......................................................................................................................... 14 3.4. Operate Mode ......................................................................................................................... 16 3.4.1. Full On Mode .................................................................................................................. 16 3.4.2. Standby Mode ................................................................................................................ 17 3.4.3. Backup Mode ................................................................................................................. 18 3.4.4. Period Mode ................................................................................................................... 20 3.4.5. AlwaysLocateTM Mode ................................................................................................... 22 3.5. RESET..................................................................................................................................... 23 3.6. UART Interface ........................................................................................................................ 24 3.7. EASY Technology.................................................................................................................... 26 3.8. Multi-tone AIC .......................................................................................................................... 26 3.9. ANTON .................................................................................................................................... 27 3.10. LOCUS .................................................................................................................................... 27 4 Antenna Interface ............................................................................................................................... 28 4.1. Antenna Specification ............................................................................................................. 28 4.2. Recommended Circuit for Antenna ......................................................................................... 29 4.2.1. Active Antenna ............................................................................................................... 29 4.2.2. Passive Antenna ............................................................................................................ 31 5 Electrical, Reliability and Radio Characteristics ............................................................................ 33 5.1. Absolute Maximum Ratings .................................................................................................... 33 5.2. Operating Conditions .............................................................................................................. 34 5.3. Current Consumption .............................................................................................................. 34 5.4. Electro-static Discharge .......................................................................................................... 35 5.5. Reliability Test ......................................................................................................................... 36 l e t l c a i e t u n Q fide n o C L76_Hardware_Design Confidential / Released 3 / 45 GNSS Module L76 Hardware Design 6 Mechanics ........................................................................................................................................... 37 6.1. Mechanical View Of The Module ............................................................................................ 37 6.2. Bottom Dimension and Recommended Footprint ................................................................... 38 6.3. Top View Of The Module ......................................................................................................... 39 6.4. Bottom View of the Module ..................................................................................................... 39 7 Manufacturing .................................................................................................................................... 40 7.1. Assembly and Soldering ......................................................................................................... 40 7.2. Moisture Sensitivity ................................................................................................................. 41 7.3. ESD Safe ................................................................................................................................. 41 7.4. Tape and Reel ......................................................................................................................... 41 7.5. Ordering Information ............................................................................................................... 42 8 Appendix Reference .......................................................................................................................... 43 l e t l c a i e t u n Q fide n o C L76_Hardware_Design Confidential / Released 4 / 45 GNSS Module L76 Hardware Design Table Index TABLE 1: FEATURE ............................................................................................................................................ 9 TABLE 2: THE PROTOCOL SUPPORTED BY THE MODULE ......................................................................... 11 TABLE 3: PIN DESCRIPTION ........................................................................................................................... 12 TABLE 4: MODULE STATE SWITCH ................................................................................................................ 16 TABLE 5: DEFAULT CONFIGURATION............................................................................................................ 17 TABLE 6: PMTK COMMAND FORMAT ............................................................................................................ 20 TABLE 7: RECOMMENDED ANTENNA SPECIFICATION ............................................................................... 28 TABLE 8: ABSOLUTE MAXIMUM RATINGS .................................................................................................... 33 l e t l c a i e t u n Q fide n o C TABLE 9: THE MODULE POWER SUPPLY RATINGS..................................................................................... 34 TABLE 10: THE MODULE CURRENT CONSUMPTION .................................................................................. 34 TABLE 11: THE ESD ENDURANCE TABLE (TEMPERATURE: 25, HUMIDITY: 45 %) ............................... 35 TABLE 12: RELIABILITY TEST ......................................................................................................................... 36 TABLE 13: TRAY PACKING .............................................................................................................................. 42 TABLE 14: ORDERING INFORMATION ........................................................................................................... 42 TABLE 15: RELATED DOCUMENTS ................................................................................................................ 43 TABLE 16: TERMS AND ABBREVIATIONS ...................................................................................................... 43 L76_Hardware_Design Confidential / Released 5 / 45 GNSS Module L76 Hardware Design Figure Index FIGURE 1: BLOCK DIAGRAM .......................................................................................................................... 10 FIGURE 2: PIN ASSIGNMENT ......................................................................................................................... 12 FIGURE 3: INTERNAL POWER CONSTRUCTION.......................................................................................... 15 FIGURE 4: CURRENT AND CONSUMPTION VERSUS VCC ......................................................................... 15 FIGURE 5: RTC SUPPLY FROM NON-CHARGEABLE BATTERY .................................................................. 19 FIGURE 6: REFERENCE CHARGING CIRCUIT FOR CHARGEABLE BATTERY .......................................... 19 FIGURE 7: SEIKO MS920SE CHARGE AND DISCHARGE CHARACTERISTICS ......................................... 20 FIGURE 8: PERIOD TIMING ............................................................................................................................. 22 l e t l c a i e t u n Q fide n o C TM FIGURE 9: ALWAYSLOCATE MODE ............................................................................................................ 23 FIGURE 10: REFERENCE RESET CIRCUIT USING OC CIRCUIT ................................................................. 24 FIGURE 11: MODULE TIMING ......................................................................................................................... 24 FIGURE 12: CONNECTION OF SERIAL INTERFACES .................................................................................. 25 FIGURE 13: RS-232 LEVEL SHIFT CIRCUIT ................................................................................................... 25 FIGURE 14: REFERENCE DESIGN WITH ACTIVE ANTENNA ....................................................................... 29 FIGURE 15: REFERENCE DESIGN FOR ACTIVE ANTENNA WITH ANTON ................................................. 30 FIGURE 16: REFERENCE DESIGN WITH PASSIVE ANTENNA .................................................................... 31 FIGURE 17: REFERENCE DESIGN FOR PASSIVE ANTENNA WITH LNA .................................................... 32 FIGURE 18: TOP VIEW AND SIDE VIEWUNIT: MM ................................................................................. 37 FIGURE 19: BOTTOM DIMENSIONUNIT: MM .......................................................................................... 38 FIGURE 20: FOOTPRINT OF RECOMMENDATIONUNIT: MM ................................................................ 38 FIGURE 21: TOP VIEW OF THE MODULE ...................................................................................................... 39 FIGURE 22: BOTTOM VIEW OF THE MODULE .............................................................................................. 39 FIGURE 23: RAMP-SOAK-SPIKE-REFLOW OF FURNACE TEMPERATURE ............................................... 40 FIGURE 24: TAPE AND REEL SPECIFICATION .............................................................................................. 41 L76_Hardware_Design Confidential / Released 6 / 45 GNSS Module L76 Hardware Design 1 Introduction This document defines and specifies L76 GNSS module. It describes L76 GNSS module hardware interface and its external application reference circuits, mechanical size and air interface. This document can help you quickly understand the interface specifications, electrical and mechanical details of L76 GNSS module. We also offer you other documents such as L76 software application notes and user guider. These documents can ensure you use L76 module to design and set up mobile applications quickly. l e t l c a i e t u n Q fide n o C L76_Hardware_Design Confidential / Released 7 / 45 GNSS Module L76 Hardware Design 2 Product Concept 2.1. General Description L76 is a single receiver module integrated with GLONASS and GPS system. It is able to achieve the industry's highest level of sensitivity, accuracy and TTFF with the lowest power consumption in a small-footprint lead-free package. The embedded flash memory provides capacity for storing user-specific configurations and allows for future updates. l e t l c a i e t u n Q fide n o C The L76 GNSS module supports multiple positions and navigation system including autonomous GPS, GLONASS, SBAS (including WAAS, EGNOS, MSAS and GAGAN), QZSS, and AGPS. Embedded with many advanced power saving modes including period, AlwaysLocateTM, standby and backup, L76 GNSS module has excellent low-power consumption in different scenes. EASY technology as the key feature of L76 is one kind of AGPS. Collecting and processing all internal aiding information like GPS time, Ephemeris, Last Position etc, the GNSS module will have a fast TTFF in either Hot or Warm start. L76 GNSS module is an SMD type module with the compact 10.1mm x 9.7mm x 2.5mm form factor, which can be embedded in your applications through the 18-pin pads. It provides necessary hardware interfaces between the module and your board. The module is fully ROHS compliant to EU regulation. L76_Hardware_Design Confidential / Released 8 / 45 GNSS Module L76 Hardware Design 2.2. Key Features Table 1: Feature Feature Implementation GNSS GPS&GLONASS Power supply Supply Voltage: 2.8V - 4.3V typical : 3.3V Power consumption Acquisition Tracking Acquisition Tracking 21 mA @ -130dBm(GPS) 15 mA @ -130dBm(GPS) 25 mA @ -130dBm(GPS+GLONASS) 18 mA @ -130dBm(GPS+GLONASS) Receiver Type GPS L1 1575.42MHz C/A Code GLONASS L1 1598.0625~1605.375 C/A Code l e t l c a i e t u n Q fide n o C Sensitivity(NOTE) Time-To-First-Fix (EASY enabled) Acquisition Reacquisition Tracking -148dBm -160dBm -163dBm Cold Start Warm Start Hot Start <15s average@-130dBm <5s average@-130dBm 1s @-130dBm Time-To-First-Fix (EASY disabled) Cold Start (Autonomous) Warm Start (Autonomous) Hot Start (Autonomous) Horizontal Position Accuracy(autonomous) <2.5 m CEP@-130dBm Update Rate Up to 10Hz,1Hz by default Accuracy of 1PPS Signal Typical accuracy <15ns (Not support time service) Time pulse width 100ms Velocity Accuracy Without Aid 0.1m/s Acceleration Accuracy Without Aid 0.1m/s Dynamic Performance Maximum Altitude 18,000m Maximum Velocity 515m/s Maximum Acceleration 4G UART Port UART Port: TXD1 and RXD1 Supports baud rate from 4800bps to 115200bps,9600bps by default UART Port is used for NMEA output, MTK proprietary messages input and firmware upgrade Temperature range Normal operation: -45C ~ +85C Storage temperature: -45C ~ +125C L76_Hardware_Design <35s average@-130dBm <30s average@-130dBm 1s@-130dBm Confidential / Released 9 / 45 GNSS Module L76 Hardware Design Size: 10.10.15 x 9.70.15 x 2.50.15mm Weight: Approx. 0.6g Physical Characteristics NOTE The sensitivity is measured with external LNA or active antenna. It might worsen by about 2 or 3dB without external LNA or only with passive antenna. 2.3. Block Diagram l e t l c a i e t u n Q fide n o C The following figure shows a block diagram of L76 GNSS module. It consists of a single chip GNSS IC which includes RF part and Baseband part, a SAW filter, a TCXO and a crystal oscillator. RF_IN Saw filter RF Front-End Integrated LNA Fractional-N Syntheszer Active Interference Cancellation PMU GNSS Engine TCXO ROM RAM VCC VCC_RF V_BCKP FORCE_ON Peripheral controller ARM7 Processor Flash UART RESET STANDBY 1PPS ANTON RTC 32.768K XTAL Figure 1: Block Diagram 2.4. Evaluation Board In order to help you use L76 GNSS module on your applications, Quectel supplies an Evaluation Board (EVB) with Micro-USB cable, active antenna and other peripherals to test the module. For more details, please refer to the document [1]. L76_Hardware_Design Confidential / Released 10 / 45 GNSS Module L76 Hardware Design 2.5. The Module Supports Protocols Table 2: The Protocol Supported by the Module Protocol Type NMEA Input/output, ASCII, 0183, 3.01 PMTK Input, MTK proprietary protocol NOTE l e t l c a i e t u n Q fide n o C Please refer to document [2] about NMEA standard protocol and MTK proprietary protocol. L76_Hardware_Design Confidential / Released 11 / 45 GNSS Module L76 Hardware Design 3 Application The module is equipped with an 18-pin 1.1mm pitch SMT pad that connects to your application platform. Sub-interfaces included in these pads are described in details in the following chapters. l e t l c a i e t u n Q fide n o C 3.1. Pin Assignment 10 GND 11 RF_IN RESET 9 VCC 8 NC 7 V_BCKP 6 STANDBY 5 1PPS 4 3 12 GND 13 ANTON 14 VCC_RF 15 NC 16 RESERVED RXD1 17 RESERVED TXD1 18 FORCE_ON GND L76 (Top View) 2 1 Figure 2: Pin Assignment 3.2. Pin Definition Table 3: Pin Description Power Supply Pin Name Pin No. I/O Description power power VCC 8 I Main supply V_BCKP 6 I Backup supply L76_Hardware_Design DC Characteristics Comment Vmax= 4.3V Vmin=2.8V Vnom=3.3V Assure load current no less than 150mA. Vmax=4.5V Vmin=1.5V Supply power for RTC domain when VCC is Confidential / Released 12 / 45 GNSS Module L76 Hardware Design Vnom=3.3V IV_BCKP=7uA@Backup mode VCC_RF powered off. Vmax=4.3V Vmin=2.8V Vnom=3.3V Usually supply power for external active antenna or LNA. If unused, keep this pin open. VCC_RF VCC 14 O Supply Power for external RF component Pin No. I/O Description DC Characteristics Comment It is low level active. If unused, keep this pin open or connect it to VCC. Comment Reset Pin Name RESET UART port Pin Name RXD1 TXD1 l e t l c a i e t u n Q fide n o C 9 I System reset VILmin=-0.3V VILmax=0.7V VIHmin=2.1V VIHmax= 3.1V Pin No. I/O Description DC Characteristics Receive data VILmin=-0.3V VILmax=0.7V VIHmin=2.1V VIHmax= 3.1V 3 I 2 O Transmit data VOLmax=0.42V VOHmin=2.4V VOHnom=2.8V Pin No. I/O Description DC Characteristics Comment 11 I RF signal input Characteristic impedance of 50 Refer to chapter 4 I/O Description DC Characteristics Comment O External LNA control pin and VOLmax=0.42V active antenna VOHmin=2.4V power control pin VOHnom=2.8V in power save mode If unused, keep this pin open. I Used to enter into or exit from standby mode It is pulled up internally. It is edge-triggered. If unused, keep this pin RF interface Pin Name RF_IN Other interface Pin Name ANTON STANDBY Pin No. 13 5 L76_Hardware_Design VILmin=-0.3V VILmax=0.7V VIHmin=2.1V Confidential / Released 13 / 45 GNSS Module L76 Hardware Design 1PPS FORCE_ ON RESERVED 4 18 O One pulse second per I Logic high will force module to be waked up from backup mode VIHmax= 3.1V open. VOLmax=0.42V VOHmin=2.4V VOHnom=2.8V Synchronized at rising edge, the pulse width is100ms. If unused, keep this pin open. VILmin=-0.3V VILmax=0.7V VIHmin=2.1V VIHmax= 3.1V Keep this pin open or pulled low before entering into backup mode. It belongs to RTC domain. If unused, keep this pin open. l e t l c a i e t u n Q fide n o C 16,17 Keep these pins open. 3.3. Power Supply VCC pin supplies power for BB, RF, I/O and RTC domain. The load current of VCC pin varies according to the VCC level, processor load and satellite acquisition. Typical VCC peak current is 40 mA (typ.) during GPS acquisition after power up. So it is important to supply sufficient current and make the power clean and stable. VCC supply ripple voltage should meet the requirement: 54 mV (RMS) max @ f = 0... 3MHz and 15 mV (RMS) max @ f > 3 MHz. You should choose the LDO without built-in output high-speed discharge function to keep long output voltage drop-down period. The decouple combination of 10uF and 100nF capacitor is recommended nearby VCC pin. The V_BCKP pin supplies power for RTC domain. A cell battery with the combination of 4.7uF and 100nF capacitor is recommended nearby V_BCKP pin. The voltage of RTC domain ranges from 1.5V to 4.5V. In order to achieve a better Time To First Fix (TTFF), RTC domain should be valid all the time. It can supply power for SRAM memory in RTC domain which contains all the necessary GPS information for quick start-up and a small amount of user configuration variables. The module's internal power construction is shown as below. VCC pin not only supplies power for PMU but also for VCC_RF and RTC domain. V_BCKP supplies power for RTC domain only. The two diode in following figure construct an OR gate supply power for RTC domain. FORCE_ON pin belongs to RTC domain. The signal which has been shown as red line in the following diagram can open and close the switch. The following action will close and open the switch: The switch will be closed by default when VCC is supplied power (VCC off on). Based on above step, FORCE_ON open or low and sending PMTK command can open the switch (full on backup). Based on above step, FORCE_ON logic high can close the switch (backup full on). L76_Hardware_Design Confidential / Released 14 / 45 GNSS Module L76 Hardware Design VCC_RF PMU VCC V_BCKP ARM Logic circuit FORCE_ON l e t l c a i e t u n Q fide n o C RTC power RTC Figure 3: Internal Power Construction The following picture shows average current and power consumption versus VCC supply voltage. It was tested in the open sky and tracking mode based on GPS&GLONASS. 70 60 50 40 Current(mA) 30 Power(mW) 20 10 0 2.8 3.1 3.3 3.5 3.7 3.9 4.1 4.3 Figure 4: Current and Consumption Versus VCC NOTE The sleep time in period backup mode and AlwaysLocateTM backup mode equals to the time in backup mode. L76_Hardware_Design Confidential / Released 15 / 45 GNSS Module L76 Hardware Design 3.4. Operate Mode The table below briefly illustrates the relationship among different operating modes of L76 GNSS module Table 4: Module State Switch Current Mode Next Mode Backup Backup Standby Full on Period Always Locate l e t l c a i e t u n Q fide n o C N/A N/A Refer to chapter 3.4.3 N/A N/A N/A N/A Standby N/A N/A Pull STANDBY high Send any data via UART1 Full on Refer to chapter 3.4.3 Pull STANDBY low PMTK161 N/A PMTK 225 PMTK225 Period N/A N/A Refer to chapter 3.4.4 N/A N/A Always locate N/A N/A Refer to chapter 3.4.5 N/A N/A NOTE Please refer to document [2] about MTK proprietary protocol for more details. 3.4.1. Full On Mode Full on mode includes tracking mode and acquisition mode. Acquisition mode is defined as the module starts to search satellites, determine visible satellites and coarse carrier frequency and code phase of satellite signals. When the acquisition is completed, it switches to tracking mode automatically. Tracking mode is defined as the module tracks satellites and demodulates the navigation data from the specific satellites. Whether the combination of VCC and V_BCKP pins is valid or VCC is valid, the module will enter into full on mode automatically and follow the default configuration as below. You can refer to chapter 3.3 about internal power construction to have a good comprehension. You also can use PMTK commands to change the configuration to satisfy the requirement. L76_Hardware_Design Confidential / Released 16 / 45 GNSS Module L76 Hardware Design Table 5: Default Configuration Item Configuration Baud rate 9600bps Protocol NMEA Update rate 1Hz SBAS Enable AIC LOCUS Comment RMC, VTG, GGA, GSA, GSV and GLL l e t l c a i e t u n Q fide n o C Enable Disable EASY technology Enable GNSS GPS+GLONASS In full on mode, the consumption will comply with the following regulation: When the module is powered on, the average current will rush to 40mA and it will last a few seconds, then the consumption will be decreased to acquisition current marked in table 1 and we defined this state as acquisition state, also it will last several minutes until it switches to tracking state automatically. The consumption in tracking state is less than acquisition. The value is also listed in table 1. Using PMTK commands can switch among multiple position system: $PMTK353,0,1*36: search GLONASS satellites only $PMTK353,1,0*36: search GPS satellites only $PMTK353,1,1*37: search GLONASS and GPS satellites 3.4.2. Standby Mode Standby mode is a low-power consumption mode. In standby mode, the internal core and I/O power domain are still active, but RF and TCXO are powered off, the module stops satellites search and navigation. UART1 is still accessible like PMTK commands or any other data, but there is no NEMA messages output. There are two ways to enter into standby mode and exit from standby mode. Using STANDBY pin: Pulling STANDBY low will make the GNSS module to enter into standby mode and releasing STANDBY which has been pulled high internally will make the module back to full on mode. Note that pulling down STANDBY pin to ground will cause the extra current L76_Hardware_Design Confidential / Released 17 / 45 GNSS Module L76 Hardware Design consumption which makes the typical standby current reach to about 600uA @ VCC=3.3V. Using PMTK command: Sending PMTK command "$PMTK161,0*28" will enter into standby mode. Sending any data via UART1 will make the module exiting from standby mode as UART1 is still accessible in standby mode. When the module exit from standby mode, it will use all internal aiding information like GPS time, Ephemeris, Last Position etc, resulting to a fastest possible TTFF in either Hot or Warm start. The typical current consumption in this way is about 500uA @VCC=3.3V in standby mode. NOTE l e t l c a i e t u n Q fide n o C Setting the customer's GPIO which control STANDBY pin as input is recommended before turning on the module to avoid entering into standby mode unexpectedly during starting the module due to its edge-triggered characteristics, after that, customer can reset the GPIO as output to control the STANDBY pin. If it is unused, keep it open. 3.4.3. Backup Mode Back up mode is a lower power consumption mode than standby mode. In this mode, the module stops to acquire and track satellites. UART1 is not accessible. But the backed-up memory in RTC domain which contains all the necessary GPS information for quick start-up and a small amount of user configuration variables is alive. Due to the backed-up memory, EASY technology is available. The type consumption in this mode is about 7uA. There are two ways to enter into backup mode and back to full on mode. Send command: "$PMTK225,4*2F" (the red line open the switch in Figure 3) to enter into backup mode forever. The only way to wake up the module is pulling the FORCE_ON high (the red line closes the switch in Figure 3). Cutting off VCC and V_BCKP present will make the module to enter into backup mode from full on mode. As long as the VCC pin is supplied power, the module will enter into full on mode immediately. But this method is not recommended. NOTE Keep FORCE_ON pin open or low before entering into backup mode or it is not available. To have a good comprehension, please refer to chapter 3.3 about internal power construction. The V_BCKP pin can be directly provided by an external capacitor or battery (rechargeable or non-chargeable). Please refer to the following figure for RTC backup reference design. L76_Hardware_Design Confidential / Released 18 / 45 GNSS Module L76 Hardware Design MODULE V_BCKP Non-chargeable Backup Battery 4.7uF RTC LDO 100nF l e t l c a i e t u n Q fide n o C Figure 5: RTC Supply from Non-chargeable Battery The V_BCKP pin does not support charging function for rechargeable battery. It is necessary to add a charging circuit for rechargeable battery. Charge Circuit VCC 1K MODULE V_BCKP Chargeable Backup Battery 4.7uF RTC LDO 100nF Figure 6: Reference Charging Circuit for Chargeable Battery Coin-type Rechargeable Capacitor such as MS920SE from Seiko can be used and Schottky diode such as RB520S30T1G from ON Semiconductor is recommended to be used here for its low voltage drop. L76_Hardware_Design Confidential / Released 19 / 45 GNSS Module L76 Hardware Design l e t l c a i e t u n Q fide n o C Figure 7: Seiko MS920SE Charge and Discharge Characteristics 3.4.4. Period Mode Period mode is a mode that can control the full on mode and standby/backup mode periodically to reduce power consumption. It contains Period standby mode and Period backup mode. The format of the command which enters into period mode is as following: Table 6: PMTK Command Format Format: $PMTK225,<Type>,<Run_time>,<Sleep_time>,<2nd_run_time>,<2nd_sleep_time>*<checksum> <CR><LF> Parameter Format Description Decimal Type=1 for Period Backup Mode Type=2 for Period Standby Mode Run_time Decimal Run_time = Full on period (ms) Sleep_time Decimal Sleep_time = Standby/Backup period (ms) 2nd_run_time Decimal 2nd_run_time=Full on period (ms) for extended acquisition in case module's acquisition fails during the Run_time Type L76_Hardware_Design Confidential / Released 20 / 45 GNSS Module L76 Hardware Design 2nd_sleep_time Decimal 2nd_sleep_time = Standby/Backup period (ms) for extended sleep in case module's acquisition fails during the Run_time Checksum Hexadecimal Hexadecimal checksum Example: $PMTK225,2,3000,12000,18000,72000*15<CR><LF> $PMTK225,1,3000,12000,18000,72000*16<CR><LF> Sending "$PMTK225,0*2B" in any time will make the module to full on mode from Period standby mode l e t l c a i e t u n Q fide n o C Pulling the FORCE_ON high and sending "$PMTK225,0*2B" immediately will make the module to full on mode from Period backup mode. Sending "$PMTK225,0*2B" in Run_time or 2nd_run_time will also make the module to full on mode from Period backup mode, but it is hard to operate and not recommended. NOTES 1. 2. Setting the customer's GPIO which control STANDBY pin as input is recommended before turning on the module to avoid entering into standby mode unexpectedly during starting the module due to its edge-triggered characteristics, after that, customer can reset the GPIO as output to control the STANDBY pin. If it is unused, keep it open. Keep FORCE_ON pin open or low before entering into period backup mode or it is not available. The following figure has shown the operation of period mode. When you send PMTK command, the module will be in the full on mode firstly. After several minute, the module will enter into the period mode and follow the parameters set by you. When the module fails to fix the position in run time, the module will switch to second run and sleep time automatically. As long as the module fixs the position again, the module will return to first run and sleep time. Note that before entering into period mode, assure the module is in the tracking mode; otherwise the module will have a risk of failure to track the satellite. If GNSS module is located in weak signal environment, it is better to set the longer second run time to ensure the success of reacquisition. The average current value can be calculated by the following formula: I period= (I tracking*T1+Istandby/backup*T2)/ (T1+T2) T1: Run time, T2: Sleep time Example: PMTK225,2,3000,12000,18000,72000*15 for period mode with 3s in tracking mode and 12s in standby mode based on GPS&GLONASS. The average current consumption is calculated below: I period=(I tracking*T1+Istandby*T2 )/(T1+T2)=(18mA*3s + 0.5mA*12s)/(3s+12s)4.0(mA) L76_Hardware_Design Confidential / Released 21 / 45 GNSS Module L76 Hardware Design PMTK225,1,3000,12000,18000,72000*16 for period mode with 3s in tracking mode and 12s in backup mode based on GPS&GLONASS. The average current consumption is calculated below: I period=(I tracking*T1+Ibackup*T2 )/(T1+T2)=(18mA*3s + 0.007mA*12s)/(3s+12s)3.6(mA) Power Full on Run time Run time Second run time Second run time Run time Run time l e t l c a i e t u n Q fide n o C Sleep time Sleep time Second sleep time Second sleep time Sleep time Sleep time Figure 8: Period Timing 3.4.5. AlwaysLocateTM Mode AlwaysLocateTM is an intelligent power saving mode. It contains alwaysLocateTM backup mode and alwaysLocateTM standby mode. AlwaysLocateTM standby mode supports the module to switch automatically between full on mode and standby mode. According to the environmental and motion conditions, the module can adaptively adjust the full on time and standby time to achieve the balance between positioning accuracy and power consumption. Sending "$PMTK225,8*23" and the module returning: "$PMTK001,225,3*35" means the module accesses alwaysLocateTM standby mode successfully. It will benefit power saving in this mode. Sending "$PMTK225,0*2B" in any time will make the module back to full on mode. AlwaysLocateTM backup mode is the similar with alwaysLocateTM standby mode. The difference is that AlwaysLocateTM backup mode switches automatically between full on mode and backup mode. The PMTK command to enter into alwaysLocateTM backup mode is "$PMTK225,9*22". Pulling FORCE_ON high and sending "$PMTK225,0*2B" immediately will make the module enter into full on mode. The position accuracy in AlwaysLocateTM mode will be degraded, especially in high speed. The following picture shows the rough consumption in different scenes. L76_Hardware_Design Confidential / Released 22 / 45 GNSS Module L76 Hardware Design l e t l c a i e t u n Q fide n o C Figure 9: AlwaysLocateTM mode Example: The average consumption of the module which is located in outdoor in static and equipped active antenna after tracking satellites is about 2.7mA in AlwaysLocateTM standby mode based on GPS&GLONASS. The average consumption of the module which is located in outdoor in static and equipped active antenna after tracking satellites is about 2.6mA in AlwaysLocateTM backup mode based on GPS&GLONASS. NOTES 1. 2. Setting the customer's GPIO which controls STANDBY pin as input is recommended before turning on the module to avoid entering into standby mode unexpectedly during starting the module due to its edge-triggered characteristics, after that, customer can reset the GPIO as output to control the STANDBY pin. If it is unused, keep it open. Keep FORCE_ON pin open or low before entering into AlwaysLocateTM backup mode or it is not available. 3.5. Reset L76 GNSS module can be restarted by driving the RESET to a low level voltage for a certain time and then releasing it. This action will force volatile RAM data loss. Note that Non-Volatile Backup RAM content is not cleared and thus fast TTFF is possible. An OC driver circuit shown as below is recommended to control the RESET. L76_Hardware_Design Confidential / Released 23 / 45 GNSS Module L76 Hardware Design RESET 4.7K Input pulse 47K Figure 10: Reference reset circuit using OC circuit l e t l c a i e t u n Q fide n o C The following picture is shown the timing of L76 module. > 2ms VCC Pulldown > 10ms VIH >2.0V RESET VIL<0.8V UART Invalid Valid Invalid Valid Figure 11: Module timing 3.6. UART Interface The module provides one universal asynchronous receiver & transmitter serial port. The module is designed as a DCE (Data Communication Equipment), following the traditional DCE-DTE (Data Terminal Equipment) connection. The module and the client (DTE) are connected through the following signal shown as following figure. It supports data baud-rate from 4800bps to 115200bps. UART port TXD1: Send data to the RXD signal line of DTE RXD1: Receive data from the TXD signal line of DTE L76_Hardware_Design Confidential / Released 24 / 45 GNSS Module L76 Hardware Design Module(DCE) Customer(DTE) UART port TXD1 TXD RXD1 RXD GND GND l e t l c a i e t u n Q fide n o C Figure 12: Connection of serial interfaces This UART port has the following features: UART port can be used for firmware upgrade, NMEA output and PMTK proprietary messages input. The default output NMEA type setting is RMC, VTG, GGA, GSA, GSV and GLL. UART port supports the following data rates: 4800, 9600, 14400, 19200, 38400, 57600, 115200. The default setting is 9600bps, 8 bits, no parity bit, 1 stop bit. Hardware flow control and synchronous operation are not supported. The UART port does not support the RS-232 level but only CMOS level. If the module's UART port is connected to the UART port of a computer, it is necessary to add a level shift circuit between the module and the computer. Please refer to the following figure. SP3238 28 25 1 3 TXD1 Module 3.3V V+ C1- GND C2+ VCC C2- V- 24 23 22 19 T1IN T2IN T3IN T4IN 17 T5IN 16 21 20 18 RXD1 C1+ 13 /R1OUT R1OUT R2OUT R3OUT T4OUT T2OUT T3OUT T1OUT T5OUT R1IN R2IN R3IN 27 2 26 3.3V 4 10 6 7 5 12 8 9 11 ONLINE 15 /STATUS 14 /SHUTDOWN 6 7 8 9 To PC serial port 1 2 3 4 5 GND Figure 13: RS-232 Level Shift Circuit L76_Hardware_Design Confidential / Released 25 / 45 GNSS Module L76 Hardware Design NOTE As GNSS module outputs more data than single GPS system. The default output NMEA types running in 4800 baud rate and 1Hz update rate will lose some data. The solution to avoid losing data in 4800 baud rate and 1Hz update rate is to decrease the output NMEA types. 9600 baud rate is enough to transmit GNSS NMEA in default settings and it is recommended. 3.7. EASY Technology l e t l c a i e t u n Q fide n o C Supplying aided information like ephemeris, almanac, rough last position, time, and satellite statuscan help improving GNSS module TTFF and the acquisition sensitivity. We call this EASY technology and The L76 GNSS module supports it. EASY technology works as embedded software which can accelerate TTFF by predicting satellite navigation messages from received ephemeris. The GNSS engine will calculate and predict orbit information automatically up to 3 days after first receiving the broadcast ephemeris, and saving the predicted information into the internal memory. GNSS engine will use this information for positioning if no enough information from satellites, so the function will be helpful for positioning and TTFF improvement. The EASY function can reduce TTFF to 5s for warm start. In this case, RTC domain should be valid. In order to gain enough broadcast ephemeris information from GNSS satellites, the GNSS module should receive the information for at least 5 minutes in the good signal condition after it fix the position. EASY function is enabled by default. The command "$PMTK869,1,0*34" can be used to disable EASY function. For more details, please refer to the document [2]. 3.8. Multi-tone AIC L76 GNSS module has a function called multi-tone AIC (Active Interference Cancellation) to decease harmonic of RF noise from Wi-Fi, Bluetooth, GSM and 3G. Up to 12 multi-tone AIC embedded in the module can provide effective narrow-band interference and jamming elimination. The GNSS signal could be demodulated from the jammed signal, which can ensure better navigation quality. AIC function is enabled by default. Opening AIC function will increase about 1mA @VCC=3.3V consumption. This function is enabled by default. The following commands can be used to set AIC function. Enable AIC function: "$PMTK286,1*23". Disable AIC function: "$PMTK286,0*22". L76_Hardware_Design Confidential / Released 26 / 45 GNSS Module L76 Hardware Design 3.9. ANTON L76 GNSS module provides a pin called ANTON which is related to module state. Its voltage level will change in different module state. When the module works in full on mode, this pin is high level, while works in standby mode, backup mode as well as sleep time in period mode and alwaysLocateTM mode, this pin is low level. Based on this characteristic, this ANTON pin can be used to control the power supply of active antenna or the enable pin of the external LNA to reduce power consumption. Please refer to chapter 3.2 for more electrical characteristics about this pin. There is an example of this pin's application described in chapter 4.2. l e t l c a i e t u n Q fide n o C 3.10. LOCUS The L76 GNSS module supports the embedded logger function called LOCUS. It can log position information to internal flash memory automatically when this function is enabled by sending PMTK command "$PMTK185,0*22". Due to this function, the host can go to sleep to save power consumption and do not need to receive the NMEA information all the time. The module can provide a log capacity of more than 16 hours. The detail procedures of this function are as following: The module has fixed the position (only 3D_fixed is available), Sending PMTK command "$PMTK184,1*22" to erase internal flash. Sending PMTK command "$PMTK185,0*22" to start log. Module logs the basic information (UTC time, latitude, longitude and height) every 15 seconds to internal flash memory. Stop logging the information by sending "$PMTK185,1*23". MCU can get the data via UART1 by sending "$PMTK622,1*29" to the module. The raw data which MCU gets has to be parsed via locus parser code provided by Quectel. For more detail, please contact Quectel FAE department. L76_Hardware_Design Confidential / Released 27 / 45 GNSS Module L76 Hardware Design 4 Antenna Interface L76 GNSS module supports both GPS and GLONASS systems. The RF signal is obtained from the RF_IN pin. The impedance of RF trace should be controlled by 50 Ohm, and the length should be kept as short as possible. l e t l c a i e t u n Q fide n o C 4.1. Antenna Specification The L76 GNSS module can be connected to a dedicated GPS/GLONASS passive or active antenna in order to receive both GPS and GLONASS satellite signals. The recommended antenna specification is given in following table. Table 7: Recommended Antenna Specification Antenna Type Specification Passive antenna GPS frequency: GLONASS frequency : VSWR: Polarization: Gain: 1575.422 MHz 16024 MHz <2 (Typ.) RHCP or Linear >0 dBi Active antenna GPS frequency: GLONASS frequency : VSWR: Polarization: Noise figure: Gain (antenna): Gain (embedded LNA): Total Gain: 1575.422 MHz 16024 MHz <2 (Typ.) RHCP or Linear <1.5dB >-2dBi 20dB (Typ.) >18dBi(Typ.) L76_Hardware_Design Confidential / Released 28 / 45 GNSS Module L76 Hardware Design 4.2. Recommended Circuit for Antenna Both active and passive antenna can be used for L76 GNSS module. 4.2.1. Active Antenna 4.2.1.1. Active Antenna without ANTON l e t l c a i e t u n Q fide n o C The following figure is a typical reference design with active antenna. In this mode, the antenna's power is from the VCC_RF. Active Antenna matching circuit L76_Module R1 0R C2 NM C1 NM L1 47nH RF_IN R2 10R VCC_RF Figure 14: Reference Design with Active Antenna C1, R1, C2 are reserved matching circuit for antenna impedance modification. By default, C1 and C2 are not mounted, R1 is 0 ohm. L76 GNSS module provides power supply for external active antenna by VCC_RF. The voltage ranges from 2.8V to 4.3V, typical value is 3.3V. If the VCC_RF voltage does not meet the requirements for powering the active antenna, an external LDO should be used. The inductor L1 is used to prevent the RF signal from leaking into the VCC_RF pin and route the bias supply to the active antenna and the recommended value of L1 is no less than 47nH. R2 can protect the whole circuit in case the active antenna is shorted to ground. L76_Hardware_Design Confidential / Released 29 / 45 GNSS Module L76 Hardware Design 4.2.1.2. Active Antenna with ANTON L76 GNSS module can also reduce power consumption by controlling the power supply of active antenna through the pin "ANTON". The reference circuit for active antenna with "ANTON" function is given as below. Active Antenna L76_Module matching circuit l e t l c a i e t u n Q fide n o C R3 RF_IN 0R C1 NM C2 NM 10R VCC_RF L1 47nH R1 Q1 Power control circuit Q2 R2 10K ANTON Figure 15: Reference Design for Active Antenna with ANTON ANTON is an optional pin which can be used to control the power supply of the active antenna. When the ANTON pin is pulled down, MOSFET Q1 and Q2 are in high impedance state and the power supply for antenna is cut off. When ANTON is pulled high, it will make Q1 and Q2 in the on-state, VCC_RF will provide power supply for the active antenna. The high and low level of ANTON pin is determined by the module's state. Please refer to chapter 3.9 for more detail. If unused, please keep ANTON pin open. For minimizing the current consumption, the value of resistor R2 should not be too small, and the recommended value is 10k ohm. L76_Hardware_Design Confidential / Released 30 / 45 GNSS Module L76 Hardware Design 4.2.2. Passive Antenna 4.2.2.1. Passive Antenna without External LNA Passive Antenna L76_Module matching circuit R1 l e t l c a i e t u n Q fide n o C 0R C2 NM C1 NM RF_IN Figure 16: Reference Design with Passive Antenna The above figure is a typical reference design with passive antenna. C1, R1, C2 are reserved matching circuit for antenna impedance modification. C1 and C2 are not mounted by default, R1 is 0 ohm. Impedance of RF trace should be controlled by 50 ohm and the length should be kept as short as possible. If an external LNA is added between passive antenna and L76 GNSS module, the total sensitivity will be improved about 3dB, and the TTFF will be shorter in weak signal, which might be helpful for better performance. 4.2.2.2. Passive Antenna with External LNA In order to improve the receiver sensitivity and reduce the TTFF, an external LNA between the passive antenna and the L76 GNSS module is recommended. The reference design is shown as below. L76_Hardware_Design Confidential / Released 31 / 45 GNSS Module L76 Hardware Design Psssive Antenna L76_Module C3 56pF matching circuit RF_IN RF OUT R1 ENABLE C2 NM C1 NM RF IN 0R VCC LNA R2 ANTON 100R R3 l e t l c a i e t u n Q fide n o C VCC_RF 100R Figure 17: Reference Design for Passive Antenna with LNA Here, C1, R1, C2 form a reserved matching circuit for passive antenna and LNA. By default, C1 and C2 are not mounted, R1 is 0 ohm. C3 is reserved for impedance matching between LNA and L76 GNSS module and the default value of C3 capacitor is 56pF which you might optimize according to the real conditions. ANTON is an optional pin which can be used to control the enable pin of an external LNA. NOTES 1. 2. The selected LNA should support both GPS and GLONASS system. The recommended parts numbers are MAX2659, BGU7007 and SKY65602. Here, MAX2659 and BGU7007 are pin to pin compatible. For more details, please contact Quectel FAE department. The power consumption of the device will be reduced by controlling "LNA ENABLE" through the pin "ANTON" of L76 GNSS module. If "ANTON" function is not used, please connect the pin "LNA ENABLE" to VCC and keep LNA always on. L76_Hardware_Design Confidential / Released 32 / 45 GNSS Module L76 Hardware Design 5 Electrical, Reliability and Radio Characteristics 5.1. Absolute Maximum Ratings l e t l c a i e t u n Q fide n o C Absolute maximum rating for power supply and voltage on digital pins of the module are listed in following table. Table 8: Absolute Maximum Ratings Parameter Min Max Unit Power supply voltage VCC -0.3 5 V Backup battery voltage (V_BCKP) -0.3 5 V Input voltage at digital pins -0.3 3.6 V 0 dBm 125 C Input power at RF_IN (PRF_IN) Storage temperature NOTE -45 Stressing the device beyond the "Absolute Maximum Ratings" may cause permanent damage. These are stress ratings only. The product is not protected against over voltage or reversed voltage. If necessary, voltage spikes exceeding the power supply voltage specification, given in table above, must be limited to values within the specified boundaries by using appropriate protection diodes. L76_Hardware_Design Confidential / Released 33 / 45 GNSS Module L76 Hardware Design 5.2. Operating Conditions Table 9: The Module Power Supply Ratings Parameter VCC IVCCP V_BCKP VCC_RF TOPR NOTES Description Conditions Min Type Max Unit Supply voltage Voltage must stay within the min/max values, including voltage drop, ripple, and spikes. 2.8 3.3 4.3 V l e t l c a i e t u n Q fide n o C Peak supply current VCC=3.3V Backup voltage supply Output section voltage 1.5 3.3 RF Full on Operating temperature -45 25 150 mA 4.5 V VCC V 85 1. This figure can be used to determine the maximum current capability of power supply. 2. Operation beyond the "Operating Conditions" is not recommended and extended exposure beyond the "Operating Conditions" may affect device reliability. 5.3. Current Consumption The values for current consumption are shown in following table. Table 10: The Module Current Consumption Parameter Max Min Type Unit IVCC@Acquisition @-130dBm(GPS) 21 mA IVCC @Tracking @-130dBm (GPS) 15 mA IVCC@Acquisition @-130dBm(GPS+GLONASS) 25 mA IVCC @Tracking @-130dBm (GPS+GLONASS) 18 mA L76_Hardware_Design Confidential / Released 34 / 45 GNSS Module L76 Hardware Design IVCC @Standby @VCC=3.3V 0.5 mA IBCKP @backup @V_BCKP=3.3V 7 uA NOTES 1. 2. The VCC_RF current is not reckoned in above consumption. The tracking current is tested in following condition: For Cold Start, 10 minutes after First Fix. For Hot Start, 15 seconds after First Fix. l e t l c a i e t u n Q fide n o C 5.4. Electro-static Discharge L76 GNSS module is an ESD sensitive device. ESD protection precautions should still be emphasized. Proper ESD handing and packaging procedures must be applied throughout the processing, handing and operation of any application. The ESD bearing capability of the module is listed in following table. Note that you should add ESD components to module pins in the particular application. Table 11: The ESD Endurance Table (Temperature: 25, Humidity: 45 %) Pin RF_IN VCC UART Others L76_Hardware_Design Contact Discharge Air Discharge 5KV 10KV 5KV 10KV 3KV 6KV 2KV 4KV Confidential / Released 35 / 45 GNSS Module L76 Hardware Design 5.5. Reliability Test Table 12: Reliability Test Test item Condition Standard Thermal shock -30C...+80C, 144 cycles GB/T 2423.22-2002 Test Na IEC 68-2-14 Na Damp cyclic +55C; >90% Rh 6 cycles for 144 hours IEC 68-2-30 Db Test heat, l e t l c a i e t u n Q fide n o C Vibration shock 5~20Hz,0.96m2/s3;20~500Hz,0.96m2/s3-3dB/oct, 1hour/axis; no function 2423.13-1997 Test Fdb IEC 68-2-36 Fdb Test Heat test 85C, 2 hours, Operational GB/T 2423.1-2001 Ab IEC 68-2-1 Test -40C, 2 hours, Operational GB/T 2423.1-2001 Ab IEC 68-2-1 Test 90C, 72 hours, Non-Operational GB/T 2423.2-2001 Bb IEC 68-2-2 Test B -45C, 72 hours, Non-Operational GB/T 2423.1-2001 A IEC 68-2-1 Test Cold test Heat soak Cold soak L76_Hardware_Design Confidential / Released 36 / 45 GNSS Module L76 Hardware Design 6 Mechanics This chapter describes the mechanical dimensions of the module. 6.1. Mechanical View Of the Module l e t l c a i e t u n Q fide n o C 9.70.15 2.50.15 8.840.10 1.00.10 9.180.10 10.10.15 Figure 18: Top View and Side ViewUnit: mm L76_Hardware_Design Confidential / Released 37 / 45 GNSS Module L76 Hardware Design 6.2. Bottom Dimension and Recommended Footprint 0.90 0.65 0.65 0.80 1.10 10.10 l e t l c a i e t u n Q fide n o C ? 0.50 7.90 0.65 0.65 9.70 Figure 19: Bottom DimensionUnit: mm 0.90 0.80 9 0.65 1.1 10 0.90 10.10 18 7.90 1 9.70 11.50 Figure 20: Footprint of RecommendationUnit: mm NOTE For EASY maintenance of this module and accessing to these pads, please keep a distance of no less than 3mm between the module and other components in host board. L76_Hardware_Design Confidential / Released 38 / 45 GNSS Module L76 Hardware Design 6.3. Top View Of The Module 1 18 l e t l c a i e t u n Q fide n o C 9 10 Figure 21: Top View of the Module 6.4. Bottom View of the Module 18 1 10 9 Figure 22: Bottom View of the Module L76_Hardware_Design Confidential / Released 39 / 45 GNSS Module L76 Hardware Design 7 Manufacturing 7.1. Assembly and Soldering L76 GNSS module is intended for SMT assembly and soldering in a Pb-free reflow process on the top side of the PCB. It is suggested that the minimum height of solder paste stencil is 130um to ensure sufficient solder volume. Pad openings of paste mask can be increased to ensure proper soldering and solder wetting over pads. It is suggested that peak reflow temperature is 235~245C (for SnAg3.0Cu0.5 alloy). Absolute max reflow temperature is 260C. To avoid damage to the module when it is repeatedly heated, it is suggested that the module should be mounted after the first panel has been reflowed. The following picture is the actual diagram which we have operated. 250 l e t l c a i e t u n Q fide n o C Preheat Heating Cooling Liquids Temperature 217 200 200 40s~60s 160 150 70s~120s 100 Between 1~3/S 50 0 50 100 150 200 250 300 s Time(s) Figure 23: Ramp-soak-spike-reflow of Furnace Temperature L76_Hardware_Design Confidential / Released 40 / 45 GNSS Module L76 Hardware Design 7.2. Moisture Sensitivity L76 GNSS module is sensitivity to moisture absorption. To prevent L76 GNSS module from permanent damage during reflow soldering, baking before reflow is required in following cases: Humidity indicator card: At least one circular indicator is no longer blue The seal is opened and the module is exposed to excessive humidity. L76 GNSS module should be baked for 192 hours at temperature 40+5/-0 and <5% RH in low-temperature containers, or 24 hours at temperature 1255 in high-temperature containers. Care should be taken that plastic tray is not heat resistant. L76 GNSS module should be taken out before preheating, otherwise, the tray maybe damaged by high-temperature heating. l e t l c a i e t u n Q fide n o C 7.3. ESD Safe L76 GNSS module is an ESD sensitive device and should be careful to handle. 7.4. Tape and Reel 28.5 1212 345 678 05 11 910 07 09 10 08 06 13 330 Out direction 100 6 PS 16.000.15 15 0. 2.000.15 0 .5 4.000.15 ?1 0.300.05 3.00? a0.15 Unit: mm Quantity per reel: 500pcs Length per reel: 8.64m 11.100.15 10.100.15 11.100.15 11.500.15 24.000.3 1.750.1 24.5 10.10? a0.15 Figure 24: Tape and Reel Specification L76_Hardware_Design Confidential / Released 41 / 45 GNSS Module L76 Hardware Design Table 13: Tray Packing Model Name L76 MOQ for MP Minimum Package:500pcs Minimum Package x4=2000pcs 500pcs Size: 370mmx350mmx56mm N.W: 0.25kg G.W: 1.00kg Size: 380mmx250mmx365mm N.W: 1.1kg G.W: 4.4kg 7.5. Ordering Information l e t l c a i e t u n Q fide n o C Table 14: Ordering Information Model Name Product Number Ordering Code L76 S2-W1087 L76-M33 L76_Hardware_Design Confidential / Released 42 / 45 GNSS Module L76 Hardware Design 8 Appendix Reference Table 15: Related Documents SN [1] [2] [3] Document name Remark l e t l c a i e t u n Q fide n o C L76_EVB _User Guide L76 EVB User Guide L76_GNSS_Protocol_Specification L76 GNSS Protocol Specification L76_Reference_Design L76 Reference Design Table 16: Terms and Abbreviations Abbreviation Description AGPS Assisted GPS AIC CEP DGPS EASY EGNOS EMC EPO ESD Active Interference Cancellation Circular Error Probable Differential GPS Embedded Assist System European Geostationary Navigation Overlay Service Electromagnetic Compatibility Extended Prediction Orbit Electrostatic Discharge GPS Global Positioning System GNSS Global Navigation Satellite System GGA GPS Fix Data GLL Geographic Position - Latitude/Longitude L76_Hardware_Design Confidential / Released 43 / 45 GNSS Module L76 Hardware Design GLONASS GLOBAL NAVIGATION SATELLITE SYSTE GSA GNSS DOP and Active Satellites GSV GNSS Satellites in View HDOP Horizontal Dilution of Precision IC Integrated Circuit I/O Input /Output Kbps LNA MSAS MOQ NMEA PDOP PMTK PPS PRN QZSS RHCP RMC SBAS SAW TTFF UART l e t l c a i e t u n Q fide n o C Kilo Bits Per Second Low Noise Amplifier Multi-Functional Satellite Augmentation System Minimum Order Quantity National Marine Electronics Association Position Dilution of Precision MTK Proprietary Protocol Pulse Per Second Pseudo Random Noise Code Quasi-Zenith Satellite System Right Hand Circular Polarization Recommended Minimum Specific GNSS Data Satellite-based Augmentation System Surface Acoustic Wave Time To First Fix Universal Asynchronous Receiver & Transmitter VDOP Vertical Dilution of Precision VTG Course over Ground and Ground Speed, Horizontal Course and Horizontal Velocity WAAS Wide Area Augmentation System Inom Nominal Current L76_Hardware_Design Confidential / Released 44 / 45 GNSS Module L76 Hardware Design Imax Maximum Load Current Vmax Maximum Voltage Value Vnom Nominal Voltage Value Vmin Minimum Voltage Value VIHmax Maximum Input High Level Voltage Value VIHmin Minimum Input High Level Voltage Value VILmax VILmin VImax VImin VOHmax VOHmin VOLmax VOLmin l e t l c a i e t u n Q fide n o C L76_Hardware_Design Maximum Input Low Level Voltage Value Minimum Input Low Level Voltage Value Absolute Maximum Input Voltage Value Absolute Minimum Input Voltage Value Maximum Output High Level Voltage Value Minimum Output High Level Voltage Value Maximum Output Low Level Voltage Value Minimum Output Low Level Voltage Value Confidential / Released 45 / 45