Rich set of peripheral support. ➢. USB 2.0 Full-speed. ➢. CAN 2.0 Controller. ➢.
SPI with upto 7 slaves. ➢. Serial Port with I2S support. ➢. Two Wire Interface (I2C)
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Navika-Exd – Fleet Management Platform with integrated GPS Features ¨
ARM7 processing core at 90MHz
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Integrated, high performance GPS engine Ø Ø Ø
16 parallel GPS channels for Acquisition and Tracking Capable of indoor positioning Extremely fast fix times
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2Mbits of internal SRAM for applications
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Rich set of peripheral support Ø Ø Ø Ø Ø Ø Ø
USB 2.0 Full-speed CAN 2.0 Controller SPI with upto 7 slaves Serial Port with I2S support Two Wire Interface (I2C) Sixteen GPIO Three Timers
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Multiple boot modes
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1” x 1.5” form-factor
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Single 3.3V input supply
Product Description The Navika-Exd is a 1”x1.5” module catering to applications that demand high performance from a GPS module at an extremely small form-factor. The Navika-Exd makes use of Accord’s AST-GPSRF RF front end and AST-230 SoC. The AST-GPSRF is a miniature GPS RF Front end designed for GPS C/A and Galileo OS band receivers. The RF chip has an in-built low noise amplifier (LNA), single down conversion stage, automatic gain controlled amplifier (AGC), on-chip IF band pass filter and a 2-bit analog-to-digital converter (ADC). In addition, the chip has in-built protection/detection circuitry for accidental short/open of the GPS antenna.
Figure 1. Navika-Exd
The AST-230 is a revolutionary digital integrated circuit that combines a high performance GPS Correlator, ARM7 core and a host of rich peripherals. This System On Chip (SoC) delivers unmatched performance in conjunction with the AST-GPSRF. The GPS Correlator executes 16 channels of acquisition and tracking on GPS signals. With a large number of internal Correlator blocks, the AST-230 is able to detect the weakest of signals in very short time frames, thereby delivering positioning data in the blink of an eye. The ARM7 core runs at 90 MHz and interfaces with several industry standard peripherals on AHB/APB bus. With an on-chip 2Mbit SRAM, running applications on the AST-230 is a cinch. Further, about 30 MIPS are available on the ARM7 to run user applications The AST-230 provides plenty of peripherals ranging from USB 2.0 OTG with Full Speed, CAN 2.0 controller, SPORT, SPI, TWI, Timers, Timing block, GPIO and Battery backed counter/RTC.
Navika-Exd Module Details
The Navika-Exd brings out some of the essential peripherals for host interface such as SPI port, TWI port, two UART ports, USB port and GPIO’s. The Navika-Exd is targeted for applications that require positioning and/or timing outputs. In addition to the user co-ordinates, Navika-Exd is capable of delivering unmatched timing accuracy. Typical applications where Navika-Exd could be integrated are – ¨
Vehicle tracking
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Security
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Geo-tagging
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Wireless base-stations
The Navika-Exd is a 1”x1.5” sized GPS system on board. It requires a single 3.3V supply and a 1.2V battery feed that would enable the user to fully exploit all its features. The module has been designed keeping all components on one side of the PCB and provides SMD pads at the bottom for electrical and mechanical connectivity. The connection details and the mechanical information are provided below.
RESERVED RESERVED RESERVED RESERVED CLK_EXT_CAL_DIV CLK_EXT_CLK_OUT CLK_CAL_1HZ CLK_EXT_CAL_IN BOOT_SLSH_ERR_VALID BOOT_FLSH_ERR_1 BOOT_FLSH_ERR_0 BOOT_MODE_1 BOOT_MODE_0 DGND GPIO2 GPIO3 GPIO4 GPIO5
1
GPIO7 GPIO1 GPIO6 GPIO8 GPIO0 DGND GPIO13 GPIO14 GPIO15 DGND JTAG_TRST JTAG_TDO JTAG_TMS JTAG_TCK JTAG_TDI DGND SPI_FLASH_CS SPI_CS SPI_CLK SPI_MISO SPI_MOSI DGND SPORT_Y_ADATA SPORT_Y_BDATA SPORT_Y_CLK SPORT_Y_FS DGND EXT_RF_VCC_3V0
Navika-Exd Module
RESERVED EXT_TIMER_CLK RESERVED RESERVED RESERVED PTTI CLK_OUT1 CLK_OUT2 CLK_OUT3 /RESET DGND TWI_SDA TWI_SCL DGND CAN_RX CAN_TX DGND UART2_CTS UART2_TX UART2_RTS UART2_RX UART1_RTS UART1_CTS UART1_TX UART1_RX DVCC_3V3 DGND VBAT_1V2
USB_VBUS USB_CID USB_DP USB_DM USB_DISCHRGVB USB_CHRGVBUS USB_DRVBUS ANT_VCC_3V0 DGNS AST_ANT_SENSE ANT_SENSE DGND GPS_IN DGNS SPORT_X_CLK SPORT_X_ADATA SPORT_X_FS SPORT_X_BDATA
Figure 2: Navika-Exd Pinouts and Mechanical Details
Navika-Exd – Connection Diagram
In order to build a complete GPS receiver using the module, all it takes are a few connections. The diagram below depicts the interconnections to be done in order to use the Navika-Exd. 1. Connect a 50W trace between the RF_IN pad and the antenna connector 2. Connect a 20W, 1W resistor between the ANT_SENSE and ANT_VCC_3V pads. This is required to sense a short circuit on the antenna power line as well as to protect the power-ground short circuit 3. An active low power ON reset of at least 25ms should be provided on the /RESET pad 4. The host communication can be tapped at the UART1_RXD and UART1_TXD lines 5. Since the AST-230 supports multiple boot modes, it is necessary to set the boot mode to boot from NOR flash. This can be done by properly terminating the BOOT_MODE_0 and BOOT_MODE_1 lines 6. Mains power of 3.3V +/- 5% should be applied at DVCC_3V3 pad. The maximum current draw of the board would be about 50mA (excluding antenna current). It is recommended to mount a decoupling capacitor of 1uF close to the DVCC_3V3 pad 7. A backup battery of 1.2V should be applied at VBAT_1V2 pad. The recharge circuitry (in case of a rechargeable battery) should be provisioned on the motherboard
RF_IN, 34 3.3V BOOT_MODE_1, 86
ANT_SENSE, 1
BOOT_MODE_0, 87
ANT_VCC, 39
GND
20ohm, 1W
Optional 20ohm resistor for Antenna Short Circuit Protection
1.2V VBAT_1V2, 47
RESET /RESET, 65 RX
3.3V UART1_RXD, 50
DVCC_3V3, 49
UART1_TXD, 51
DGND, 6, 10, 16, 22, 27, 35, 48, 58, 61, 64, 88
TX
GND
Figure 3. Circuit Interconnection using Navika-Exd module
Specifications of Navika-Exd Module Processor Processor core Instruction speed Host bus clock speed Peripheral clock speed GPS System Specifications Channels Acquisition Sensitivity
ARM7-TDMI 90MHz 45MHz (max) 22.5MHz (max)
Tracking Sensitivity Hot Start TTFF (with valid ephemeris, almanac, position and time estimate) Warm Start TTFF (with almanac, position and time estimate) Cold Start TTFF (without almanac, time, or position) Position Accuracy Velocity Accuracy 1PPS Accuracy Memory Internal Memory Battery Backed Expansion SPI Configuration Clock Slave selects TWI Configuration Data transfer UART Configuration Baud Rate Message Formats USB Configuration Functionality Endpoints GPIO Configuration Features Others Antenna Sense
Electrical Supply Current Battery Current
16 Acquisition, 16 Tracking -155dBm (Hot start, 1SV @ -144dBm) -160dBm (Reacquisition) -160dBm 1 sec (typical) switch OFF/ON cycle less than 1 hour 35 sec (typical) 40 sec (typical) 10 m (90% without S/A) 0.1 m/sec (90% without S/A) +/- 12ns (2s without errors) 2Mbits SRAM 32Kbits SRAM External SRAM / Serial Flash CS, CLK, MOSI, MISO 22.5MHz Upto 7 SDA, SCLK 400Kbits / sec TX, RX (2 sets) Up to 1Mbps 5, 6, 8 data bits, even / odd parity Full-Speed DM, DP, VBUS Device Control endpoint: 1 RX endpoints: 7 TX endpoints: 7 Upto 16 GPIO (multiplexed with SPI Slave selects) Independently programmable as input or output Capable of detecting external edge / level sensitive interrupts AST-400 can sense an open circuit on the active antenna line by monitoring the drop across an external resistor. The value of the resistor needs to be designed in accordance with the antenna current. 50mA @ 3.3V 8mA @ 1.2V
Table 1. Specifications of Navika-Exd
Accord Software & Systems Pvt. Ltd. 37, K.R. Colony, Domlur Layout, Bangalore - 560 071. INDIA. Tel: +91 - 80 2535 0105 Fax: +91 - 80 2535 2723 Website: www.accord-soft.com
