Module multi-GNSS Venus 828F

Module multi-GNSS à puce unique, de haute performance et faible coût qui cible les applications mobile pour les consommateurs.


Spécifications constructeur

Features

  • Supports GPS, Beidou, QZSS, SBAS
  • Uses external BMI160 IMU for dead-reckoning
  • Optional BMP280 for exceptional altitude accuracy
  • Dead Reckoning solution without need of electrical connection to vehicle
  • -148dBm cold start sensitivity
  • -165dBm tracking sensitivity
  • 29 second cold start TTFF
  • 5 second TTFF with AGPS
  • 1 second hot start
  • 5m accuracy
  • Multipath detection and suppression
  • Jamming detection and mitigation
  • Complete receiver in 7mm x 7mm x 1.4mm size
  • Pb-free RoHS compliant

Technical Specifications

Receiver Type L1 GPS / QZSS / SBAS + B1 Beidou C/A code
167 channel Venus 8 engine
Accuracy Position 2.5m CEP
Velocity 0.1m/sec
Timing 10ns
Open Sky TTFF 29 second cold start
3.5 second with AGPS
1 second hot start
Update Rate 1Hz
Dynamics 4G
Operational Limits Altitude < 18,000m*1, Velocity < 515m/s*1
Datum Default WGS-84
Interface UART LVTTL level
Baud Rate 4800 / 9600 / 38400 / 115200
Protocol NMEA-0183 V3.01, GGA, GLL, GSA, GSV, RMC, VTG, ZDA
SkyTraq Binary
Main Supply Voltage 2.8V ~ 3.6V
Backup Voltage 2.5V ~ 3.6V
Operating Temperature -40 ~ +85 deg-C
Storage Temperature -40 ~ +125 deg-C
Package LGA31 7mm x 7mm x 1.4mm, 0.8mm pitch

 

Current Consumption

Mode

Current Consumption

(mA @ 3.3V)

External Switching Regulator

(90% efficiency)

Internal Switching Regulator

(75% efficiency)

Internal LDO

Regulator

GPS/Beidou Acquisition 31 37 75
Tracking 27 32 64
GPS Acquisition 25 30 63
Tracking 19 22 43

 

Block Diagram

Pin-out Diagram

 

 

Pin-out Definition

Pin Number Signal Name Type Description
1 GPIO3 / P1PPS bidir 1 pulse per second output. Active after position fix; goes HIGH for about 800usec, 3.3V LVTTL (default) Or general purpose I/O pin
2 GPIO5 / SDA Bidir

General purpose I/O pin, 3.3V LVTTL

Or I2C serial data

For connecting to BMI160 and BMP280

3 GPIO30 / MS_MOSI Bidir

General purpose I/O pin, 3.3V LVTTL

Or SPI master/slave data output Default not used

4 GPIO31 / MS_MISO Bidir

General purpose I/O pin, 3.3V LVTTL

Or SPI master/slave data input Default not used

5 GPIO28 / MS_CSN Bidir

General purpose I/O pin, 3.3V LVTTL

Or SPI master/slave chip select Default not used

6 GPIO0 / STS Bidir Navigation status indicator (default) Or General purpose I/O. 3.3V LVTTL
7 RXD0 Input

Received input of the asynchronous UART port. Used to input binary command to the GPS receiver. 3.3V LVTTL

Add 4.7K series resistor if putting Venus828F to sleep by shutting off main power supply.

       
8 TXD0 Output

Transmit output of the asynchronous UART port. Used to output standard NMEA-0183 sentence or response to input binary command. 3.3V LVTTL

Add 4.7K series resistor if putting Venus828F to sleep by shutting off main power supply.

9 RTCOUT Output RTC inverting buffer output
10 RTCIN Input RTC inverting buffer input
11 V12O_RFLDO Power Output RF 1.2V LDO output
12 V12I_RF Power Input RF 1.2V input
13 RFGND Power RF section system ground
14 RFIN Input RF signal input
15 RFGND Power RF section system ground
16 BOOT_SEL Bidir

Boot mode selection. Pull-high or pull-low

1: execute from internal Flash

0: execute from internal ROM

17 RSTN Input Active LOW reset input, 3.3V LVTTL
18 GPIO29 / MS_SCK Output

General purpose output pin, 3.3V LVTTL

Or SPI master/slave clock Default not used

19 GPIO4 / SCL Bidir

General purpose I/O pin, 3.3V LVTTL

Or I2C SCL clock

For connecting to BMI160 and BMP280

20 GND Power System ground
21 V33I Power Input Main voltage supply input, 3.0V ~ 3.6V
22 V12O_LDO Power Output 1.2V LDO output
23 V12I Power Input 1.2V power input
24 V_BAT Power Input Supply voltage for internal backup SRAM, 2.5V ~ 3.6V. V_BAT should be powered by non-volatile supply voltage. Maximum V_BAT current draw when V33I is removed is 35uA. Must not be left unconnected. DR calibration data will be lost if V_BAT is not powered.
25 V12I_DCDC Input Switching regulator 1.2V sense input
26 GND Power System ground
27 V33I_DCDC Power Input Switching regulator power input, 3.0V ~ 3.6V
28 SW_DCDC Power Output Switching regulator output
29 ADCIN2 Input ADC input. Unused.
30 RFGND Power RF section system ground
31 RFGND Power RF section system ground

 

DC Characteristics of Digital Interface

Parameter Min. Typ. Max. Units
Input Low Voltage     0.8 Volt
Input High Voltage 2.0     Volt
Output Low Voltage, Iol = 4 ~ 7.8mA     0.4 Volt
Output High Voltage, Ioh = 4.6 ~ 15.4mA 2.4     Volt

 

Mechanical Dimension

 

 

 

 

 

Recommended Reflow Profil

 

 

 

 

 

 

VENUS-828F APPLICATION CIRCUIT (minimum configuration)

 

 

 

 

 

VENUS-828F APPLICATION CIRCUIT (maximum configuration)

 

 

 

 

 

 

APPLICATION CIRCUIT INTERFACE SIGNALS

P1PPS :                   1 pulse per second time-mark (3.3V LVTTL)
RXD :                      UART input (3.3V LVTTL)
TXD :                      UART output (3.3V LVTTL)
VCC33 :                  Main 3.3V power input
V_BAT :                 Backup power supply
ANT_PWR            Active antenna bias voltage

 

APPLICATION INFORMATION

  1. For fast-rising power supply, a simple series R/C reset delay to pin-17, RSTN, as indicated in the application circuit is suitable. For system having slow-rising power supply, a reset IC providing 2~5ms reset duration may be necessary.
  2. For using Venus828F with active antenna directly, one with gain in range of 15~20dB and noise figure < 2dB can be used.
  3. When using passive antenna, an external LNA with gain in range of 15dB ~ 20dB and NF<1.5 should be used.
  4. Like BGA device, the Venus828F is moisture sensitive. It needs to be handled with care to void damage from moisture absorption and SMT re-flow. The device should be baked for 24 hours at 125-degC before mounting for SMT re-flow if it has been removed from the protective seal for more than 48 hours.

     

  5. If hot plug/remove power and UART serial interface, add 4.7K-ohm series resistor to pin-7 RXD0 and pin-8 TXD0 to improve ESD protection and avoid issues.

 

SLEEP MODE

For application requiring sleep mode, it can be implemented using regulator with enable control as below figure shows. To put Venus828F to sleep, the power to Venus828F is cut off by disabling the regulator via host processor GPIO pin. In sleep mode, VBAT consume less than 40uA. Fast start up operation is provided by keeping supply voltage to VBAT constant, retaining the internal data and keep RTC running while Venus828F is put to sleep or when supply 3.3V power is removed.

 

 

For applications needing sleep mode but cannot have extra cost of adding a rechargeable backup supply battery, it can be implemented as below figure shows. It will provide fast start up when Venus828F is put to sleep and awakened, but will cold start every time when the 3.3V supply voltage is removed and re-applied again.

 

 

 

 

Alternatively VBAT can also be connected to a MCU GPIO pin that always output HIGH of 3.3V if the MCU is always ON.
When using sleep mode, add 4.7K series resistor on pin-7 RXD0 and pin-8 TXD0 to reduce leakage current; also make host side pin connecting to pin-7 RXD0 high impedance if possible.

 

MOUNTING CONSIDERATION

Although the PCB populated with Venus828F-ODR, BMI160 and optional BMP280 can be mounted in any orientation, its performance relies on stable sensor location and orientation with respect to the vehicle. The PCB needs to be securely mounted in the vehicle.

 

CALIBRATION OF DR

Venus828F-ODR performs calibration of gyro bias and odometer scale automatically using GPS. Customer is not required to perform calibration at installation.

For product testing or benchmarking, the following procedure steps can achieve efficient calibration quickly after a short period of time:

  1. Find a open sky place.
  2. Start Venus828F-ODR and stand still for 60 seconds until position fix is achieved.
  3. Drive straight for 500m at speed of at least 40km/hr.
  4. For next 3 minutes, drive straight and make at least 360-deg turns (either two 90-degrees left turns and right turns, or four left turns, or four right turns) then drive straight for at least another 300m.

 

NMEA OUTPUT DESCRIPTION

The output protocol supports NMEA-0183 standard. The implemented messages include GGA, GLL, GSA, GSV, VTG, RMC, ZDA and GNS messages. The NMEA message output has the following sentence structure:
$aaccc,c–c*hh<CR><LF>

The detail of the sentence structure is explained in Table 1.

 

Table 1: The NMEA sentence structure

Character HEX Description
“$” 24 Start of sentence.
Aaccc   Address field. “aa” is the talker identifier. “ccc” identifies the sentence type.
“,” 2C Field delimiter.
c–c   Data sentence block.
“*” 2A Checksum delimiter.
Hh   Checksum field.
<CR><LF> 0D0A Ending of sentence. (carriage return, line feed)

 

Table 2: Overview of SkyTraq receiver’s NMEA messages for Venus828F

$GPGGA Time, position, and fix related data of the receiver.
$GPGLL Position, time and fix status.

$GPGSA

$BDGSA

Used to represent the ID’s of satellites which are used for position fix. When GPS satellites are used for position fix, $GPGSA sentence is output. When Beidou satellites are used for position fix, $BDGSA sentence is output.

$GPGSV

$BDGSV

Satellite information about elevation, azimuth and CNR, $GPGSV is used for GPS satellites, while $BDGSV is used for Beidou satellites
$GPRMC Time, date, position, course and speed data.
$GPVTG Course and speed relative to the ground.
$GPZDA UTC, day, month and year and time zone.

This is with GP pre-fix NMEA talker ID. Can use binary command 0x4B to set GP or GN pre-fix NMEA talker ID.

 

The formats of the supported NMEA messages are described as follows:

GGA – Global Positioning System Fix Data

Time, position and fix related data for a GPS receiver.

Structure:
$GPGGA,hhmmss.sss,ddmm.mmmm,a,dddmm.mmmm,a,x,xx,x.x,x.x,M,,,,xxxx*hh<CR><LF>

1                2                3               4               5  6  7   8   9              10    11

Example:
$GPGGA,111636.932,2447.0949,N,12100.5223,E,1,11,0.8,118.2,M,,,,0000*02<CR><LF>

Field Name Example Description
1 UTC Time 111636.932 UTC of position in hhmmss.sss format, (000000.000 ~ 235959.999)
2 Latitude 2447.0949

Latitude in ddmm.mmmm format

Leading zeros transmitted

3 N/S Indicator N Latitude hemisphere indicator, ‘N’ = North, ‘S’ = South
4 Longitude 12100.5223

Longitude in dddmm.mmmm format

Leading zeros transmitted

5 E/W Indicator E Longitude hemisphere indicator, ‘E’ = East, ‘W’ = West
6

GPS quality indicator

 

1

GPS quality indicator

0: position fix unavailable

1: valid position fix, SPS mode

2: valid position fix, differential GPS mode

3: GPS PPS Mode, fix valid

4: Real Time Kinematic. System used in RTK mode with fixed integers

5: Float RTK. Satellite system used in RTK mode. Floating integers

6: Estimated (dead reckoning) Mode

7: Manual Input Mode

8: Simulator Mode

7 Satellites Used 11 Number of satellites in use, (00 ~ 28)
8 HDOP 0.8 Horizontal dilution of precision, (00.0 ~ 99.9)
9 Altitude 108.2 mean sea level (geoid), (-9999.9 ~ 17999.9)
10 DGPS Station ID 0000

Differential reference station ID, 0000 ~ 1023

NULL when DGPS not used

11 Checksum 02  

 

GLL Latitude/Longitude

Latitude and longitude of current position, time, and status.

Structure:
$GPGLL,ddmm.mmmm,a,dddmm.mmmm,a,hhmmss.sss,A,a*hh<CR><LF>

1                 2             3                 4               5         6  7   8

Example:
$GPGLL,2447.0944,N,12100.5213,E,112609.932,A,A*57<CR><LF>

Field Name Example Description
1 Latitude 2447.0944

Latitude in ddmm.mmmm format

Leading zeros transmitted

2 N/S Indicator N

Latitude hemisphere indicator

‘N’ = North

‘S’ = South

3 Longitude 12100.5213

Longitude in dddmm.mmmm format

Leading zeros transmitted

4 E/W Indicator E

Longitude hemisphere indicator

‘E’ = East

‘W’ = West

5 UTC Time 112609.932

UTC time in hhmmss.sss format (000000.000 ~

235959.999)

6 Status A Status, ‘A’ = Data valid, ‘V’ = Data not valid
7 Mode Indicator A

Mode indicator

‘N’ = Data not valid

‘A’ = Autonomous mode

‘D’ = Differential mode

‘E’ = Estimated (dead reckoning) mode

‘M’ = Manual input mode

‘S’ = Simulator mode

8 Checksum 57  

 

GSA GNSS DOP and Active Satellites

GPS receiver operating mode, satellites used in the navigation solution reported by the GGA or GNS sentence and DOP values.

Structure:
$GPGSA,A,x,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,xx,x.x,x.x,x.x*hh<CR><LF>

1   2  3    3   3   3   3     3     3     3    3   3   3   3   4    5    6     7

Example:
$GPGSA,A,3,05,12,21,22,30,09,18,06,14,01,31,,1.2,0.8,0.9*36<CR><LF>

Field Name Example Description
1 Mode A

Mode

‘M’ = Manual, forced to operate in 2D or 3D mode

‘A’ = Automatic, allowed to automatically switch 2D/3D

2 Mode 3

Fix type

1  = Fix not available

2  = 2D

3  = 3D

3 Satellite used 1~12

05,12,21,22,30

,09,18,06,14,0

1,31,,

01 ~ 32 are for GPS; 33 ~ 64 are for WAAS (PRN minus

87); 193 ~ 197 are for QZSS; 01 ~ 37 are for Beidou (BD

PRN). GPS and Beidou satellites are differentiated by the GP and BD prefix. Maximally 12 satellites are included in each GSA sentence.

4 PDOP 1.2 Position dilution of precision (00.0 to 99.9)
5 HDOP 0.8 Horizontal dilution of precision (00.0 to 99.9)
6 VDOP 0.9 Vertical dilution of precision (00.0 to 99.9)
7 Checksum 36  

 

GSV GNSS Satellites in View

Number of satellites (SV) in view, satellite ID numbers, elevation, azimuth, and SNR value. Four satellites maximum per transmission.

Structure:
$GPGSV,x,x,xx,xx,xx,xxx,xx,…,xx,xx,xxx,xx *hh<CR><LF>

1  2   3    4   5      6    7       4   5      6   7      8

Example:
$GPGSV,3,1,12,05,54,069,45,12,44,061,44,21,07,184,46,22,78,289,47*72<CR><LF>
$GPGSV,3,2,12,30,65,118,45,09,12,047,37,18,62,157,47,06,08,144,45*7C<CR><LF>
$GPGSV,3,3,12,14,39,330,42,01,06,299,38,31,30,256,44,32,36,320,47*7B<CR><LF>

Field Name Example Description
1 Number of message 3 Total number of GSV messages to be transmitted (1-5)
2 Sequence number 1 Sequence number of current GSV message
3 Satellites in view 12 Total number of satellites in view (00 ~ 20)
4 Satellite ID 05

01 ~ 32 are for GPS; 33 ~ 64 are for WAAS (PRN minus

87); 193 ~ 197 are for QZSS; 01 ~ 37 are for Beidou (BD

PRN). GPS and Beidou satellites are differentiated by the GP and BD prefix. Maximally 4 satellites are included in each GSV sentence.

5 Elevation 54 Satellite elevation in degrees, (00 ~ 90)
6 Azimuth 069 Satellite azimuth angle in degrees, (000 ~ 359 )
7 SNR 45

C/No in dB (00 ~ 99)

Null when not tracking

8 Checksum 72  

 

RMC Recommended Minimum Specific GNSS Data

Time, date, position, course and speed data provided by a GNSS navigation receiver.

Structure:
$GPRMC,hhmmss.sss,A,dddmm.mmmm,a,dddmm.mmmm,a,x.x,x.x,ddmmyy,,,a*hh<CR><LF>

1      2            3                   4               5               6  7      8        9           10    11

Example:
$GPRMC,111636.932,A,2447.0949,N,12100.5223,E,000.0,000.0,030407,,,A*61<CR><LF>

Field Name Example Description
1 UTC time 0111636.932

UTC time in hhmmss.sss format (000000.000 ~

235959.999)

2 Status A

Status

‘V’ = Navigation receiver warning

‘A’ = Data Valid

3 Latitude 2447.0949

Latitude in dddmm.mmmm format

Leading zeros transmitted

4 N/S indicator N

Latitude hemisphere indicator

‘N’ = North

‘S’ = South

5 Longitude 12100.5223

Longitude in dddmm.mmmm format

Leading zeros transmitted

6 E/W Indicator E

Longitude hemisphere indicator

‘E’ = East

‘W’ = West

7 Speed over ground 000.0 Speed over ground in knots (000.0 ~ 999.9)
8 Course over ground 000.0 Course over ground in degrees (000.0 ~ 359.9)
9 UTC Date 030407 UTC date of position fix, ddmmyy format
10 Mode indicator A

Mode indicator

‘N’ = Data not valid

‘A’ = Autonomous mode

‘D’ = Differential mode

‘E’ = Estimated (dead reckoning) mode

‘M’ = Manual input mode

‘S’ = Simulator mode

11 checksum 61  

VTG Course Over Ground and Ground Speed

The Actual course and speed relative to the ground.

Structure:
GPVTG,x.x,T,,M,x.x,N,x.x,K,a*hh<CR><LF>

1              2        3        4   5

Example:
$GPVTG, 000.0,T,,M,000.0,N,0000.0,K,A*3D<CR><LF>

Field Name Example Description
1 Course 000.0 True course over ground in degrees (000.0 ~ 359.9)
2 Speed 000.0 Speed over ground in knots (000.0 ~ 999.9)
3 Speed 0000.0

Speed over ground in kilometers per hour (0000.0 ~

1800.0)

4 Mode A

Mode indicator

‘N’ = not valid

‘A’ = Autonomous mode

‘D’ = Differential mode

‘E’ = Estimated (dead reckoning) mode

‘M’ = Manual input mode

‘S’ = Simulator mode

5 Checksum 3D  

 

STI,20 Dead Reckoning Status message
Structure:
PSTI,xx,x,x,x,xx,x,x,x,xxx.xx,xx.xx,xx.xx,x.xx*xx<CR><LF>

1   2   3 4 5   6 7   8      9        10         11      12    13

Example:
$PSTI,20,1,1,1,32,A,0,1,821.95,20.73,-13.45,6.63*40<CR><LF>

Field No. Example Format Unit Description
1 20 numeric Proprietary message identifier: 20
2 1 numeric

DR Calibration Status

1: calibrated

0: not calibrated

3 1 numeric

Gyro Calibrate Status

1: calibrated

0: not calibrated

4 1 numeric

Sensor input available

1: available

0: not available

5 32 numeric Pulse

ADR: odometer pulse count

ODR: 0

6 A character

Position Mode indicator:

A=GPS fix,

N = Data not valid,

E = Estimated(dead reckoning) mode

7 0 numeric

Backward Status

ADR  1: activated, moving backward

0: normal, moving forward

ODR  0

8 1 numeric

Antenna detection (Reserved)

1: antenna available

0: antenna not available

9 821.95 numeric 0.002V Z-axis gyro bias
10 20.73 numeric cm/pulse

ADR: odometer scaling factor

ODR: 100

11 -13.45 numeric Deg/sec Z-axis rotation rate
12 6.63 numeric m

ADR: distance moved per second

ODR: 0

13 40 hexadecimal Checksum

 

Ordering Information

Part Number Description
Venus828F-ODR Flash version multi-GNSS-ODR receiver module