MN1818 Highly-integrated GPS Receiver Module

Transcription

1 1 Description The Micro Modular Technologies MN1818 Global Positioning System (GPS) Receiver is a highly-integrated, 12-channel receiver with fast-acquisition hardware intended for OEM applications. The MN1818 is complete with integrated RF filtering, flash memory and TCXO. The single 3.3-volt power supply requires less than 150 mw total and the built-in antenna power circuit allows for a simple, direct connection to an active antenna. By incorporating the complexity of the RF signal chain into the module, the user only needs to be concerned with routing the antenna signal into the module. The receiver tracks GPS satellites at the L1 frequency (1.575GHz) and computes position, time and velocity. The user needs only provide suitable power and a GPS signal and the MN1818 will output the navigation solution in the widely-used NMEA-0183 format. The 12-channel receiver allows all satellites in view to be tracked, providing an over-determined solution to minimize position jumps caused by individual satellite blockage. The fast-acquisition hardware design greatly reduces the time for signal acquisition when the receiver is initially powered up. The MN1818 is machine placeable by standard surface mount equipment and is available in tape and reel. A metal shield is provided for RF protection and for automated nozzle pickup. The MN1818 is supported by an evaluation kit including software, along with reference designs to speed OEM development. 1.1 Features - Complete 12-channel GPS receiver including integrated RF filtering, flash memory and TCXO - Integrated antenna power for simple connection to an active antenna - Single, 3.3-volt supply consumes less than 150 mw total power for extended battery life - Small 17.7mm by 19.2mm by 2.9mm package - Fast-acquisition design for rapid position determination under all startup and operating conditions. - Extended commercial temperature operation (-20 C to +85 C) - Standard NMEA-0183 serial messaging - Pb free RoHS compliant - Supported by hardware and software development kits MN1818 (Lid Removed) 1.2 Block Diagram Flash LNA RF Baseband SAW TCXO Port 0 Port 1 RTC (opt) GPIO (opt) Figure 1 - MN1818 Block Diagram Micro Modular Technologies Pte. Ltd.

2 1.3 GPS Performance Acquisition Time Cold start TTFF (no time, no position, no ephemeris) Hot start TTFF (time, position and ephemeris, -130dBm signal) Fast Start TTFF (time accurate to 10msec, position and ephemeris, -130dBm signal) Reacquisition Typical 42 seconds (95% confidence) 8 seconds (95% confidence) <4 seconds (95% confidence) 2 seconds (95% confidence) Table 1 Acquisition Performance Position Accuracy CEP (50%) Typical <3.0 meters Table 2 Position Accuracy Sensitivity Tracking Acquisition (Cold Start, <5 minutes TTFF, 95% confidence) Typical -151 dbm -142 dbm 2 Environmental 2.1 Operating Temperature Humidity Altitude Table 3 Sensitivity -20 C to +85 C Up to 95% non-condensing or a wet bulb temperature of +35 C, whichever is less feet to 60,000 feet Table 4 Operating Requirements 2.2 Storage Temperature Humidity Altitude Shock Shock (in shipping container) -40 C to +85 C Up to 95% non-condensing or a wet bulb temperature of +35 C, whichever is less feet to 60,000 feet 18G peak, 5 millisecond duration 10 drops from 75 cm onto concrete floor Table 5 Storage Requirements Micro Modular Technologies Pte. Ltd. Page 2 of 16

3 3 Electrical 3.1 Module Pin-out Pin Name Description 1 ANT RF input 2 GND Ground 3 GND Ground 4 GND Ground 5 GND Ground 6 NC Leave floating 7 EXTRTC_SCL SCL of ext RTC, otherwise leave floating 8 NC Leave floating or tie to ground through 100 ohms 9 GND Ground 10 EXTRTC_INT2 INT2 of ext RTC, otherwise leave floating 11 EXTRTC_SDA SDA of ext RTC, otherwise leave floating 12 GND Ground 13 NC Leave floating 14 TX0 Serial Tx Output for UART 0 15 Valid Fix GPS Valid Fix 16 RX0 Serial Rx Input for UART 0 17 RESET Reset 18 GND Ground 19 VCC Regulated 3.3V supply to module 20 SERBOOT Serial Boot 21 1PPS 1 PPS signal 22 TX1 Serial Tx Output for UART1 23 RX1 Serial Rx Input for UART1 24 NC Leave floating 25 GND Ground 26 GND Ground 27 GND Ground 28 RTC_XIN Connect to 32kHz crystal or INT1 of ext RTC or leave floating 29 RTC_XOUT Connect to 32kHz crystal or leave floating 30 GND Ground 31 GND Ground 32 GND Ground Table 6 MN1818 Pin-out Micro Modular Technologies Pte. Ltd. Page 3 of 16

4 3.2 Power Supply The MN1818 is designed to operate from a single supply voltage of 3.0 to 3.3 volts. The main 3.3 volt supply is fed to the VCC pin of the MN1818. Decoupling is provided by a single 10uF ceramic or tantalum capacitor. Voltage Current (typical) Current (maximum) 3.0VDC to 3.3VDC 50 ma 65 ma Table 7 Main Power Supply 3.3 RF Interface RF Input The MN1818 accepts a standard L1 GPS signal from a passive or active antenna on the RF Input (ANT pin). The antenna pin of the MN1818 supplies VDC for an active antenna. If a passive antenna is used, either the end user must guarantee the passive antenna appears as a DC open, or a DC blocking capacitor must be added between the ANT lead and the antenna. Otherwise permanent damage to the MN1818 will result. Signal Level Frequency Return Loss Noise Figure Impedance -150 dbm to -125 dbm typical L1 ( MHz) Better than -9 db ~ 3 db 50 ohms nominal Table 8 RF Signal Characteristics Burnout Protection The MN1818 can accept signal levels up to 20dBm with a DC voltage of +6VDC on the RF input pin without permanent damage to the module. Micro Modular Technologies Pte. Ltd. Page 4 of 16

5 3.3.3 Jamming Performance J/S vs Frequency for Loss of Sensitivity nominal GPS level of -135 dbm J/S db loss 2 db loss 5 db loss Frequency (MHz) Figure 2 Jamming Performance 3.4 Signal Interface Digital Interface Levels VCC is nominally 3.0 Vdc. VIH(min) VIH(max) VIL(min) VIL(max) VOH(min) VOH(max) VOL(min) VOL(max) 0.7 x VCC VCC Vdc -0.3 Vdc 0.3 x VCC 0.8 * VCC VCC 0 Vdc 0.22 * VCC Table 9 Digital I/O Interface Levels Micro Modular Technologies Pte. Ltd. Page 5 of 16

6 3.4.2 Serial Interface Two serial data ports provide data communications to and from the MN Supported data formats and bit rates The MN1818 data format is 8 bits, no parity, and 1 stop bit. The default bit rate is specified by the software loaded into flash. However, the user can change it from 4800 bps to 115kbps. If SERBOOT is pulled to active (low) upon reset or power-up, the serial port defaults to 9600 bps MN1818 Pin Definitions Pin 1: ANT See Section Pin 7: External RTC SCL If an external RTC is desired, connect the SCL line of the Seiko S-35390A RTC to this pin, with a 10K pullup to VCC. If no external RTC is used, leave this line floating Pin 10: External RTC INT2 If an external RTC is desired, connect the INT2 line of the Seiko S-35390A RTC to this pin, with a 10K pullup to VCC. If no external RTC is used, leave this line floating Pin 11: External RTC SDA If an external RTC is desired, connect the SDA line of the Seiko S-35390A RTC to this pin, with a 10K pullup to VCC. If no external RTC is used, leave this line floating Pin 14: TX0 The MN1818 implements two full duplex asynchronous serial UART ports. This signal is the output for the first UART and is normally used to output navigation and satellite status information from the receiver in NMEA format. In the idle condition, this pin is at logic 1. If the driving circuitry is powered independently of the MN1818, ensure this pin is not driven to logic 1 when the supply to the MN1818 is removed Pin 15: GPS Valid Fix Pin 15 is used to indicate that the receiver has acquired a valid fix Pin 16: RX0 The MN1818 implements two full duplex asynchronous serial UART ports. This signal is the input for the first UART and is normally used to input commands to the receiver. As a second function, if SERBOOT is pulled to active (low), then RX0 receives LOD formatted programming information after reset or power up. Micro Modular Technologies Pte. Ltd. Page 6 of 16

7 In the idle condition, this pin is driven at logic 1. If the driving circuitry is powered independently of the MN1818, ensure this pin is not driven to logic 1 when the supply to the MN1818 is removed Pin 17: RESET An active low is used to reset MN1818. This line must be pulled low whenever VCC falls out of spec to prevent flash memory corruption. The RESET low pulse width should be greater than 15 msec Pin 19: VCC See Section Pin 20: SERBOOT SERBOOT is a digital input. For normal operation, SERBOOT is high and the MN1818 will start executing code from on-board flash upon system reset or power-up. If SERBOOT is active (low), then the MN1818 will enter boot mode upon system reset or power-up to receive programming information in LOD format. This feature can be used to download a flash re-programmer into on board RAM to update or change flash code. The state of the SERBOOT line is only read upon power up or system reset. Refer to section 4.1 for further information Pin 21: 1PPS The 1PPS signal is a one-pulse-per-second (1PPS) signal active when the fix is valid Pin 22: TX1 The MN1818 implements two full duplex asynchronous serial UART ports. This signal is the output for the second UART. In the idle condition, this pin is at logic 1. If the driving circuitry is powered independently of the MN1818, ensure this pin is not driven to logic 1 when the supply to the MN1818 is removed Pin 23: RX1 This signal is the input for the second UART and may by used to input commands or additional information to the receiver. In the idle condition, this pin is driven at logic 1. If the driving circuitry is powered independently of the MN1818, ensure this pin is not driven to logic 1 when the supply to the MN1818 is removed Pin 28: RTC IN If use of the internal RTC is desired, connect this pin to one side of a KHz clock crystal and a shunt capacitor returned to the 3 volt DC supply. See section 7 for additional information on the RTC crystal and recommended capacitors. If an external KHz clock signal is available, it may be presented at this pin. The logic levels must match the logic levels of the MN1818. If an external RTC is desired, connect the INT1 line of the Seiko S-35390A RTC to this pin, with a 10K pullup to VCC. Micro Modular Technologies Pte. Ltd. Page 7 of 16

8 Otherwise leave this pin floating Pin 29: RTC OUT If use of the internal RTC is desired, connect this pin to one side of a KHz clock crystal and a shunt capacitor returned to the 3 volt DC supply. See section 7 for additional information on the RTC crystal and recommended capacitors. Otherwise leave this pin floating. 4 Software Interface 4.1 Programming the on-board flash The on-board flash device can be reprogrammed to update the firmware on the MN1818, or to replace the firmware with a customized version. The SERBOOT line, which is normally held in high state, is pulled active (low) and the power cycled or a reset issued. The typical procedure for re-flashing the MN1818 is to use the MMT-supplied utility to verify proper connection to the device, then download a RAM based flash utility, which upon startup will change the bit rate 115K BPS, download the flash file and then verify the flash. Serial port 0 will issue a hexadecimal $55 (ASCII upper case U) at 9600 bps. MMT supplies a flash programming utility that runs on a standard PC-compatible machine running the Windows operating system. The procedure for reprogramming the flash consists of the following steps: 1. Pull SERBOOT line low. 2. Reset the MN1818 by power cycling or sending a reset signal. 3. Detect the hexadecimal $ Using the MMT flash utility, download the flash loader program into on-board RAM. 5. Using the MMT flash utility, erase the on-board flash. 6. Using the MMT flash utility, download the new firmware image and program into the on board flash. 7. Pull SERBOOT line high. 8. Reset the MN1818 by power cycling or sending a reset signal. 9. If flash is programmed correctly, the MN1818 will execute the new software code. Micro Modular Technologies Pte. Ltd. Page 8 of 16

9 4.2 NMEA Standard Output Messages The MN1010 sends the following NMEA-0183 v3.0 standard sentences: ID Description Orion GGA GPS fix data Y (D) GSA DOP and active satellites Y (D) GSV Satellites in view Y (D) RMC Recommended Minimum GNSS Data Y (D) GLL GPS Position Latitude & Longitude Y VTG Course over ground and ground speed Y ZDA Time and date Y DTM Datum Reference Y D = Enabled by default Table 10 Standard NMEA Output Sentences 4.3 NMEA Proprietary Output Message The MN1010 sends the following NMEA proprietary sentences: Orion ID Description echo Echo of input command $PUNV,CFG_R Response to CONFIG command $PUNV,ERR Error response Table 11 Proprietary NMEA Output Sentences 4.4 NMEA Proprietary Commands The MN1010 recognizes the following NMEA proprietary commands: ID Description $PUNV,GETCONFIG Read configuration parameters $PUNV,CONFIG Set configuration parameters $PUNV,SLEEP Enter sleep mode $PUNV,START Start Navigation $PUNV,STOP Stop Navigation Table 12 Proprietary NMEA Commands For detailed information regarding these messages, please refer to the NMEA User Manual. Micro Modular Technologies Pte. Ltd. Page 9 of 16

10 5 EMI/EMC 5.1 EMI Requirements As the MN1818 is a component used on a circuit board assembly, it is not required nor is it specified to comply with EMI or EMC regulations. 5.2 Receiver Frequency Plan The MN1818 implements a single down-conversion quadrature IF receiver which then is fed into the digital baseband processor The TCXO frequency is MHz The local oscillator frequency is MHz The IF frequency is MHz Baseband Processor Clock Frequency is MHz. 6 Power Supply Decoupling and Switching A single decoupling capacitor should be placed as closed to the VCC pin of the MN1818 GPS receiver module as possible. We recommend a minimum of 10uF at the VCC pin. 7 RTC Crystal Specification Frequency Type Load capacitance Shunt capacitors KHz Tuning fork crystal 12.5 pf (see below) The series combination of the input and output shunt capacitor must equal the load capacitance for the selected RTC crystal. When calculating the capacitor values, it is important to consider the 3 pf per pin capacitance of the MN1818 device. The other end of the shunt capacitors must be tied to the VCC power supply to ensure proper RTC startup. Table 13 RTC Crystal Specs 8 Referenced Documents MMT NMEA User Manual for Orion MN1818 Design Guidelines MN1818 Evaluation Kit User Guide Table 14 Referenced Documents for MN1818 Data Sheet Micro Modular Technologies Pte. Ltd. Page 10 of 16

11 9 Packaging and Marking Information 9.1 Component Marking 9.2 Packaging Drawing Figure 3 Marking The MN1818 is packaged as a 32-pin LGA package (2 mm pitch) Figure 4 Mechanical Outline Micro Modular Technologies Pte. Ltd. Page 11 of 16

12 Figure 5 MN1818 Pad Arrangement Micro Modular Technologies Pte. Ltd. Page 12 of 16

13 9.3 Recommended PCB Footprint Figure 6 Recommended Footprint (View from Top) Micro Modular Technologies Pte. Ltd. Page 13 of 16

14 9.4 Tape and Reel Information The MN1818 is provided in standard tape and reel, with 1K devices per reel. Figure 7 Carrier Tape Dimensions 32.4 measured at hub min ± measured at hub Figure 8 Reel Dimensions (all dimensions in mm) Micro Modular Technologies Pte. Ltd. Page 14 of 16

15 9.5 Recommended Reflow Profile Figure 9 Reflow Profile Preheating Rate is 2.5 C/s Soaking Temperature is 140 C to 170 C Soaking Time 80 s Peak Temperature is 260 C Reflow time over Liquidus is 60 s Cool down rate is 2.5 C/s. 10 Ordering Information The ordering part numbers are contained in the table below: Ordering Part Number Description MN1818-RO MN1818 in tape & reel with Orion Software MN1818-TO MN1818 in tube with Orion Software Table 15 Ordering information Micro Modular Technologies Pte. Ltd. Page 15 of 16

16 11 Notices All reference and informational documents (including marketing information, specifications, reference designs, etc.) are provided for information only and are subject to change without notice. Reasonable efforts have been made in the preparation of these documents to assure their accuracy, however Micro Modular Technologies Pte Ltd. assumes no liability resulting from errors or omissions in these, or any document, or from the use of the information contained herein. Micro Modular Technologies Pte Ltd. reserves the right to make changes in the product design and specifications as needed and without notification to its users. Please check our website for the most current documentation. All information contained herein is the property of Micro Modular Technologies Pte Ltd. and may not be copied or reproduced, other than for your information, without prior written consent. 12 Contact Information Corporate Headquarters Micro Modular Technologies Pte. Ltd. No. 3, Ubi Avenue 3, #03-02 Crocodile House, Singapore Tel: (65) Fax: (65) Americas and Europe Micro Modular Technologies Americas Creekside Lane Longmont, CO 80503, U.S.A. Tel: (1) Fax: (1) Korea Office Micro Modular Technologies Korea 4th Fl, Pyung-ik Bldg, Youngtong-Dong, Paldal-Gu, Suwon-City, Kyunggi-Do, Korea For a list of Regional Sales Representatives, please see our web page: Tel : (82) sales@micro-modular.com Document no: MN1818_DS_ Micro Modular Technologies Pte. Ltd. Page 16 of 16