Tracker SoM Datasheet (pre2)

This is a preliminary datasheet and is subject to change

SoM

Functional description

Overview

The AssetTracker SoM is a System-on-a-Module (SoM) with:

  • LTE Cat 1 (EMEAA) or LTE Cat M1 (North America) cellular modem
  • GNSS (supports GPS, SBAS, QZSS, GLONASS, BeiDou, and Galileo) with up to 1.8m accuracy and untethered dead-reckoning
  • Support for CAN bus and 5V power for CAN devices
  • Built-in Inertial Measurement Unit (IMU)
  • Castellated module can be reflow soldered to your base board, and is available on an evaluation board or carrier board

Features

  • GNSS u-blox Neo M8U for GNSS with on-board dead-reckoning for up to 1.8m CEP50 GPS accuracy
    • Supports GPS L1C/A, SBAS L1C/A, QZSS L1C/A, QZSS L1-SAIF, GLONASS L1OF, BeiDou B1I, Galileo E1B/C
    • Support for battery-backup for almanac and ephemeris data
  • Quectel BG96-NA modem
    • LTE Cat M1 module for North America (United States, Canada, and Mexico)
    • 3GPP E-UTRA Release 13
    • LTE FDD bands supported: 2, 4, 12, 13
  • Quectel EG91-EX modem
    • LTE Cat 1 module for EMEAA region
    • 3GPP E-UTRA Release 13
    • Cat 1 bands supported: 1, 3, 7, 8, 20, 28
    • Support for Europe only at this time
  • Nordic Semiconductor nRF52840 SoC
    • ARM Cortex-M4F 32-bit processor @ 64MHz
    • 1MB flash, 256KB RAM in SoC
    • Bluetooth 5: 2 Mbps, 1 Mbps, 500 Kbps, 125 Kbps
    • Supports DSP instructions, HW accelerated Floating Point Unit (FPU) calculations
    • ARM TrustZone CryptoCell-310 Cryptographic and security module
    • Up to +8 dBm TX power (down to -20 dBm in 4 dB steps)
    • NFC-A tag
  • Wi-Fi location: on-board ESP32 offers SSID scanning for using third-party Wi-Fi location services
  • PMIC (Power Management IC) and Fuel Gauge
  • On-module additional 8MB SPI flash
  • CAN Bus: on-board, integrated CAN Bus controller and transceiver making it ideal for fleet and micromobility
  • Boost Converter to power 5V CAN devices from a 3.6V battery
  • RTC: Battery-backed external real-time clock
  • Watchdog Timer: integrated hardware WDT
  • 10 Mixed signal GPIO (8 x Analog, 10 x Digital, UART, I2C, SPI)
  • USB 2.0 full speed (12 Mbps)
  • JTAG (SWD) pins
  • Support for external RGB status LED
  • Support for external Reset and Mode buttons
  • On-module MFF2 Particle SIM
  • Bluetooth chip antenna on module, switchable to use U.FL connector in software.
  • Five on-module U.FL connectors for cellular, GNSS, BLE, Wi-Fi, and alternative GNSS.
  • Castellated module designed to be reflow soldered to your own custom base board, or pre-populated on a Particle Evaluation Board or Carrier Board.
  • FCC, IC, and CE certified
  • RoHS compliant (lead-free)

Interfaces

Block diagram

Power

The Tracker SoM can be powered via the VIN (3.88V-12VDC) pin, over USB, or a LiPo battery.

VIN

The input voltage range on VIN pin is 3.88VDC to 12VDC. When powering from the VIN pin alone, make sure that the power supply is rated at 10W (for example 5 VDC at 2 Amp). If the power source is unable to meet this requirement, you'll need connect the LiPo battery as well. An additional bulk capacitance of 470uF to 1000uF should be added to the VIN input when the LiPo Battery is disconnected. The amount of capacitance required will depend on the ability of the power supply to deliver peak currents to the cellular modem.

LiPo

This pin serves two purposes. You can use this pin to connect a LiPo battery (either directly or using a JST connector), or it can be used to connect an external DC power source (and this is where one needs to take extra precautions). When powering it from an external regulated DC source, the recommended input voltage range on this pin is between 3.6V to 4.4VDC. Make sure that the supply can handle currents of at least 3Amp. This is the most efficient way of powering the module since the PMIC bypasses the regulator and supplies power to the module via an internal FET leading to lower quiescent current.

When powered from a LiPo battery alone, the power management IC switches off the internal regulator and supplies power to the system directly from the battery. This reduces the conduction losses and maximizes battery run time. The battery provided with the module is a Lithium-Ion Polymer battery rated at 3.7VDC 1,800mAh. You can substitute this battery with another 3.7V LiPo with higher current rating. Remember to never exceed this voltage rating and always pay attention to the polarity of the connector. A LiPo battery with internal protection circuits is recommended.

Typical current consumption is around 180mA and up to 1.8A transients at 5VDC. In deep sleep mode, the quiescent current is 130uA [this value may change] (powered from the battery alone).

The MAX17043 fuel gauge is only compatible with single cell lithium-ion batteries. The state-of-charge (SoC) values will not be accurate with other battery chemistries.

A battery temperature sensor can be added if desired. Connect a negative temperature coefficient thermistor to the TS pin and GND. Charge suspends when the TS pin is out of range. A 103AT-2 thermistor is recommended.

VBUS

VBUS is connected to the USB detect pin of nRF52840 to enables the USB interface. The recommended input voltage range is between 4.35V to 5.5V DC. It is also connected to the bq24195 PMIC to allow for DPDM, detection of the power capacity of the USB port.

3V3 Pin

This pin is the output of the on-board 3.3V switching regulator that powers the microcontroller and the peripherals. This pin can be used as a 3.3V power source with a max load of 800mA. Unlike the Photon, this pin CANNOT be used as an input to power the module.

RTC_BAT

This is the supply to the real-time clock battery backup. 1.4 to 3.6V.

Voltage Typical Current Maximum Current Unit
3.0V 56 330 nA
1.8V 52 290 nA

If the RTC battery is not used, connect RTC_BAT to ground.

GNSS_BAT

This is the supply for maintaining the u-blox GNSS ephemeris and almanac data when removing power. This can use the same battery as RTC_BAT, can be a super-capacitor, or can be omitted. 1.5 to 3.6V. Typical current is 15 uA.

PMID

This pin is the output of the internal boost regulator of the PMIC that can source 5.1VDC from the battery in OTG (On The Go) mode. This feature is useful when your circuitry needs a 5V source from the module when powered by the battery alone.

The confusing bit about this pin is that it will continue to provide 5.1VDC but only when the input voltage (VIN) is between 3.6V to 5.1VDC. As soon as the input voltage exceeds this limit, the PMID starts tracking that voltage. For example if VIN = 9VDC, the PMID will be 9VDC and NOT 5.1VDC. So you need to be careful when using it as a source for powering your external circuitry. The max current draw on this pin is 2.1A but is not recommended due to thermal limitations of the circuit board.


Antennas

There are a number of U.FL antenna connectors on the Tracker SoM:

Label Purpose
GNSS u-blox GNSS antenna (GPS)
CELL Quectel cellular modem antenna
WIFI Wi-Fi antenna for Wi-Fi geolocation (optional)1
BLE External Bluetooth (optional)2
GNSS/DIV Quectel GNSS antenna (optional)1

1Not supported in initial release.

2There is a BLE chip antenna on the module, the external BLE antenna is optional.

There is no U.FL connector for NFC. If you wish to use the NFC tag feature, you'll need to add an antenna or antenna connector on your base board.

  • The antenna placement needs to follow some basic rules, as any antenna is sensitive to its environment. Mount the antenna at least 10mm from metal components or surfaces, ideally 20mm for best radiation efficiency, and try to maintain a minimum of three directions free from obstructions to be able to operate effectively.
  • Needs tuning with actual product enclosure and all components.
  • For the BLE antenna, it is recommended to use a 2.4 GHz single-frequency antenna and not a 2.4 GHz + 5 GHz antenna, so as to avoid large gain at the frequency twice of 2.4 GHz which can cause the second harmonic radiation of 2.4 GHz to exceed standards.

Peripherals and GPIO

There are 10 exposed GPIO lines labeled A0-A7, TX, and RX. These multi-function pins can be configured for use as GPIO or other interfaces like SPI and I2C.

Shared Peripherals Qty Input(I) / Output(O)
Digital 10 (max) I/O
Analog (ADC) 8 (max) I
UART 1 I/O
SPI 1 I/O
I2C 1 I/O
PWM 10 (max)1 O
Peripheral Type Qty Input(I) / Output(O)
USB 1 I/O
NFC Tag 1 O
CAN Bus 1 I/O

1PWM is divided into three PWM groups. Each group must share the same frequency, but can have different periods.

Note: All GPIO are only rated at 3.3VDC max. CAN bus has a higher voltage rating.

JTAG (SWD)

The AssetTracker SoM exposes the nRF52 SWD interface on the following pins. The Evaluation Board connects these pins to the 2x5 connector used on the Argon and Boron to easily connect the Particle Debugger.

# Pin Function Connected To Description
22 SWDIO JTAG nRF52 nRF52 MCU SWDIO
23 SWDCLK JTAG nRF52 nRF52 MCU SWDCLK
24 SWO JTAG nRF52 nRF52 MCU SWO

This interface can be used to debug your code or reprogram your bootloader, device OS, or the user firmware.

Memory map

nRF52840 Flash Layout Overview

  • Bootloader (48KB, @0xF4000)
  • User Application (128KB, @0xD4000)
  • System (656KB, @0x30000)
  • SoftDevice (192KB)

External SPI Flash Layout Overview (DFU offset: 0x80000000)

  • OTA (1500KB, @0x00689000)
  • Reserved (420KB, @0x00620000)
  • FAC (128KB, @0x00600000)
  • Reserved (2MB @0x00400000)
  • LittleFS (4MB, @0x00000000)

Pins and connectors

SoM Labeled

Circular labels are as follows:

Label Purpose
1 Quectel cellular modem antenna
2 Wi-Fi antenna for Wi-Fi geolocation (optional)
3 External Bluetooth (optional)
4 Built-in Bluetooth chip antenna
5 Quectel GNSS antenna (optional)
6 u-blox GNSS antenna (GPS)
7 u-blox Neo M8 GNSS (GPS)
8 Quectel cellular modem

SoM Pin description

# Pin Function Connected To Description
Right Side
1 GND POWER Ground
2 GNSS_BAT POWER IN GNSS Battery backup for GNSS
3 GNSS_RESET IO GNSS & IOEX GNSS hardware reset. Can be controlled by this pin or software.
4 GNSS_VBUS USB PWR GNSS GNSS USB power. Optional.
5 GNSS_P USB D+ GNSS GNSS USB interface D+. Optional.
6 GNSS_N USB D- GNSS GNSS USB interface D-. Optional.
7 GNSS_PULSE OUT GNSS GNSS time pulse output. Can be used for a GPS fix LED.
8 GND POWER Ground
9 NC Leave unconnected.
10 GND POWER Ground
11 WIFI_EN IO WIFI & IOEX ESP32 enable. Can be controlled by this pin or software.
12 WIFI_BOOT IO WIFI & IOEX ESP32 boot mode. Can be controlled by this pin or software.
13 WIFI_TXD OUT WIFI ESP32 serial TX
14 WIFI_RXD IN WIFI ESP32 serial TX
15 CELL_VBUS USB PWR CELL Cellular modem USB power. Optional.
16 CELL_D+ USB D+ CELL Cellular modem USB interface D+. Optional.
17 CELL-D- USB D- CELL Cellular modem USB interface D-. Optional.
18 NC SOM18 Leave unconnected.
19 NC SOM19 Leave unconnected.
20 NC SOM20 Leave unconnected.
21 NC SOM21 Leave unconnected.
22 SWDIO JTAG nRF52 nRF52 MCU SWDIO
23 SWDCLK JTAG nRF52 nRF52 MCU SWDCLK
24 SWO JTAG nRF52 nRF52 MCU SWO
25 GND POWER Ground
26 NFC2 NFC nRF52 nRF52 NFC antenna. Supports NFC tag mode only. Optional.
27 NFC1 NFC nRF52 nRF52 NFC antenna. Supports NFC tag mode only. Optional.
28 RGB_BLUE RGB LED nRF52 Common anode RGB status LED, blue. Optional.
29 RGB_GREEN RGB LED nRF52 Common anode RGB status LED, green. Optional.
30 RGB_RED RGB LED nRF52 Common anode RGB status LED, red. Optional.
31 GND POWER Ground
32 MODE INPUT nRF52 External MODE button input, active low. Optional.
33 RESET INPUT nRF52 External RESET button input, active low. Optional.
34 NC SOM34 Leave unconnected.
35 NC SOM35 Leave unconnected.
36 NC SOM36 Leave unconnected.
37 NC SOM37 Leave unconnected.
38 A7 IO nRF52 A7, D7, SS, WKP
39 A6 IO nRF52 A6, D6, SPI SCK
40 A5 IO nRF52 A5, D5, SPI MISO
41 A4 IO nRF52 A4, D4, SPI MOSI
42 GND POWER Ground
Top Side
43 GND POWER Ground
44 NC SOM44 Leave unconnected.
45 3V3 POWER OUT TPS62291 3.3V power output. 1000 mA maximum include nRF52 and other peripheral use.
46 TS IN PMIC Battery temperature sensor
47 PMID POWER OUT PMIC PMIC power output in OTG mode.
48 GND POWER Ground
49 VIN POWER IN PMIC Power input 3.88VDC to 12VDC.
50 STAT OUT PMIC PMIC charge status. Can be connected to an LED. Active low. Optional.
51 VBUS POWER IN PMIC & nRF52 nRF52 USB power input. Can be used as a power supply instead of VIN.
52 GND POWER Ground
53 LI+ POWER PMIC Connect to Li-Po battery. Can power the device or be recharged by VIN or VBUS.
Left Side
54 GND POWER Ground
55 A0 IO nRF52 A0 D0 Wire SDA
56 A1 IO nRF52 A1 D1 Wire SCL
57 A2 IO nRF52 A2 D2 Serial1 CTS
58 A3 IO nRF52 A3 D3 Serial1 RTS
59 NC SOM59 Leave unconnected.
60 NC SOM60 Leave unconnected.
61 NC SOM61 Leave unconnected.
62 NC SOM62 Leave unconnected.
63 AGND POWER nRF52 nRF52 analog ground. Can connect to regular GND.
64 CAN_N CAN CAN CAN Data-
65 CAN_P CAN CAN CAN Data+
66 CAN_5V XCL9142F40 5V power out, 0.8A maximum. Can be controlled by software.
67 GND POWER Ground
68 MCU-D- USB D- nRF52 MCU USB interface D-. Optional.
69 MCU_D+ USB D+ nRF52 MCU USB interface D+. Optional.
70 GND POWER Ground
71 MCU_RX IO nRF52 Serial RX, GPIO D9
72 MCU_TX IO nRF52 Serial TX, GPIO D8
73 RTC_BAT POWER AM18X5 RTC/Watchdog battery +. Connect to GND if not using.
74 RTC_BTN IN AM18X5 RTC EXTI. Can use as a wake button.
75 GND POWER Ground
76 NC SOM76 Leave unconnected.
77 NC SOM77 Leave unconnected.
78 NC SOM78 Leave unconnected.
79 NC SOM79 Leave unconnected.
80 NC SOM80 Leave unconnected.
81 NC SOM81 Leave unconnected.
82 NC SOM82 Leave unconnected.
83 CELL_GPS_RX IN CELL Cellular modem GPS serial RX data.
84 CELL_GPS_TX OUT CELL Cellular modem GPS serial TX data.
85 CELL_RI OUT CELL Cellular modem ring indicator output.
86 GND POWER Ground
87 CELL_GPS_RF RF CELL Cellular modem GPS antenna. Optional.
88 GND POWER Ground
89 GND POWER Ground
90 GNSS_BOOT GNSS u-blox GNSS boot mode
91 GNSS_ANT_PWR GNSS u-blox GNSS antenna power
92 GNSS_LNA_EN GNSS u-blox GNSS LNA enable or antenna switch
93 GND POWER Ground
94 GNSS_RF GNSS GNSS antenna.
95 GND POWER Ground

Pin numbers match the triangular numbers in the graphic above.

nRF52 pin assignments

SoM Pin GPIO Analog Other PWM nRF Pin
55 D0 A0 Wire SDA1 Group 0 P0.03
56 D1 A1 Wire SCL1 Group 0 P0.02
57 D2 A2 Serial1 CTS Group 0 P0.28
58 D3 A3 Serial1 RTS Group 0 P0.30
41 D4 A4 SPI MOSI Group 1 P0.31
40 D5 A5 SPI MISO Group 1 P0.29
39 D6 A6 SPI SCK Group 1 P0.04
38 D7 A7 SPI SS, WKP Group 1 P0.05
72 D8 Serial1 TX Group 2 P0.06
71 D9 Serial1 RX Group 2 P0.08

1Pull-up resistors are not included. When using as an I2C port, external pull-up resistors are required.

System peripheral GPIO

Name Description Location
BTN MODE Button P1.13
PMIC_INT PMIC Interrupt P0.26
LOW_BAT_UC Fuel Gauge Interrupt IOEX 0.0
RTC_INT Real-time clock Interrupt P0.27
BGRST Cellular module reset P0.7
BGPWR Cellular module power P0.8
BGVINT Cellular power on detect P1.14
BGDTR Cellular module DTR IOEX 1.5
CAN_INT CAN interrupt P1.9
CAN_RST CAN reset IOEX 1.6
CAN_PWR 5V boost converter enable IOEX 1.7
CAN_STBY CAN standby mode IOEX 0.2
CAN_RTS0 CAB RTS0 IOEX 1.4
CAN_RTS1 CAN RTS1 IOEX 1.2
CAN_RTS2 CAN RTS2 IOEX 1.3
SEN_INT IMU interrupt P1.7
ANT_SW1 BLE antenna switch P1.15
GPS_PWR u-blox GNSS power IOEX 0.6
GPS_INT u-blox GNSS interrupt IOEX 0.7
GPS_BOOT u-blox GNSS boot mode IOEX 1.0
GPS_RST u-blox GNSS reset IOEX 1.1
WIFI_EN ESP32 enable IOEX 0.3
WIFI_INT ESP32 interrupt IOEX 0.4
WIFI_BOOT ESP32 boot mode IOEX 0.5

Status LED

The Tracker SoM does not have an on-module RGB system status LED. We have provided its individual control pins for you to connect an LED of your liking. This will allow greater flexibility in the end design of your products.

Device OS assumes a common anode RGB LED. One common LED that meets the requirements is the Cree CLMVC-FKA-CL1D1L71BB7C3C3 which is inexpensive and easily procured. You need to add three current limiting resistors. With this LED, we typically use 1K ohm current limiting resistors. These are much larger than necessary. They make the LED less blinding but still provide sufficient current to light the LEDs. If you want maximum brightness you should use the calculated values - 33 ohm on red, and 66 ohm on green and blue.

A detailed explanation of different color codes of the RGB system LED can be found here.

Technical specifications

Absolute maximum ratings [1]

Parameter Symbol Min Typ Max Unit
Supply Input Voltage VIN-MAX +17 V
Supply Input Current IIN-MAX-L 1 A
Battery Input Voltage VLiPo +6 V
Supply Output Current I3V3-MAX-L 800 mA
Storage Temperature Tstg -30 +75 °C
ESD Susceptibility HBM (Human Body Mode) VESD 2 kV
CAN Supply Current 500 mA

1 Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

Supply voltages

Parameter Symbol Min Typ Max Unit
Supply voltages
Supply Input Voltage VIN 3.88 12 V
VBUS USB supply voltage VUSB -0.3 +5.8 V
Supply Output Voltage VIN +4.8 V
Supply Output Voltage V3V3 +3.3 V
LiPo Battery Voltage VLiPo +3.6 +4.4 V
CAN Supply Voltage 5 V
CAN Supply Current 500 mA
I/O pin voltage
VI/O IO -0.3 +3.6 V
NFC antenna pin current
INFC1/2 NFC1/NFC2 80 mA
Radio
BT RF input level (52840) 10 dBm
Environmental
Storage temperature -40 +85 °C

1 Stresses beyond those listed under absolute maximum ratings may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under recommended operating conditions is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

Parameter Symbol Min Typ Max Unit
Supply voltages
Supply Input Voltage VIN +3.8 +12.0 V
VBUS USB supply voltage VUSB +4.35 +5.0 +5.5 V
Environmental
Normal operating temperature1 -20 +25 +753 °C
Extended operating temperature2 -40 +85 °C
Humidity Range Non condensing, relative humidity 95 %

Notes:

1 Normal operating temperature range (fully functional and meet 3GPP specifications).

2 Extended operating temperature range (RF performance may be affected outside normal operating range, though module is fully functional)

3 The maximum operating temperature is 75°C on the B523 (Quectel) but is 65°C on the B402 (u-blox LTE M1). For compatibility across modules, limit this to 65°C.


GNSS specifications

  • u-blox NEO-M8U untethered dead reckoning module including 3D inertial sensors
  • SPI Interface
  • Supports GPS L1C/A, SBAS L1C/A, QZSS L1C/A, QZSS L1-SAIF, GLONASS L1OF, BeiDou B1I, and Galileo E1B/C
Parameter Specification
Dynamics operational limit1 ≤ 4g
Altitude operational limit1 50000 m
Velocity operational limit1 500 m/s
Velocity accuracy2 0.5 m/s
Heading accuracy2 1 degree
Max navigation update rate3 30 Hz
Max navigation latency3 < 10 ms
Parameter GPS & GLONASS GPS GLONASS BeiDou Galileo
Time-To-First Fix5 Cold start 26s 30s 31s 39s 57s
Hot start 1.5s 1.5s 1.5s 15.s 1.5s
Aided start6 3s 3s 3s 7s 7s
Sensitivity 78 Tracking & Navigation -160 dBm -160 dBm -157 dBm -160 dBm -154 dBm
Reacquisiton -160 dBm -159 dBm -156 dBm -155 dBm -152 dBm
Cold Start -148 dBm -147 dBm -145 dBm -143 dBm -133 dBm
Hot Start -157 dBm -156 dBm -155 dBm -155 dBm -151 dBm
Horizontal positioning accuracy Autonomous 9 2.5m 2.5m 4.0m 3.0m TBC10
With SBAS11 1.5m 1.5m - - -
Altitude accuracy With SBAS12 3.5m 3.0m 7.0m 5.0m -

1 Configured for Airborne < 4g platform

2 50% at 30 m/s

3 High navigation rate mode

5 All satellites at -130 dBm, except Galileo at -127 dBm

6 Dependent on aiding data connection speed and latency

7 Demonstrated with a good external LNA

8 Configured min. CNO of 6 dB/Hz, limited by FW with min. CNO of 20 dB/Hz for best performance

9 CEP, 50%, 24 hours static, -130 dBm, > 6 SVs

10 To be confirmed when Galileo reaches full operational capability

11 CEP, 50%, 24 hours static, -130 dBm, > 6 SVs

12 CEP, 50%, 24 hours static, -130 dBm, > 6 SVs

GNSS GPIO:

Name Description Location
GPS_PWR u-blox GNSS power IOEX 0.6
GPS_INT u-blox GNSS interrupt IOEX 0.7
GPS_BOOT u-blox GNSS boot mode IOEX 1.0
GPS_RST u-blox GNSS reset IOEX 1.1

CAN Specifications

  • Microchip MCP25625 CAN Controller with Integrated Transceiver
  • SPI Interface
  • Implements CAN2.0B (ISO11898-1)
  • Implements ISO-11898-2 and ISO-11898-5 standard physical layer requirements
  • Up to 1 Mb/sec operation
  • 3 transmit buffers with prioritization and abort features
  • 2 receive buffers
  • 6 filters and 2 masks with optional filtering on the first 2 data bytes
  • CAN bus pins are disconnected when device is unpowered
  • High-ESD protection on CANH and CANL, meets IEC61000-4-2 up to ±8 kV
  • Very low standby current, 10 uA, typical
  • 5V step-up converter (XCL9142F40CER), 500 mA
  • CAN terminator resistor is not included

CAN GPIO:

Name Description Location
CAN_INT CAN interrupt P1.9
CAN_RST CAN reset IOEX 1.6
CAN_PWR 5V boost converter enable IOEX 1.7
CAN_STBY CAN standby mode IOEX 0.2
CAN_RTS0 CAB RTS0 IOEX 1.4
CAN_RTS1 CAN RTS1 IOEX 1.2
CAN_RTS2 CAN RTS2 IOEX 1.3

CANH, CANL Absolute Maximum Ratings:

Parameter Maximum
DC Voltage at CANH, CANL -58V to +58V
Transient Voltage on CANH, CANL (ISO-7637) -150V to +100V
ESD Protection on CANH and CANL Pins (IEC 61000-4-2) ±8 kV
ESD Protection on CANH and CANL Pins (IEC 801; Human Body Model) ±8 kV

CAN Tranceiver Characteristics

Parameter Symbol Min Typ Max Unit Conditions
Supply Input Voltage VDDA 5.0 V
Supply Current IDD 5 10 mA Recessive; VTXD = VDDA
45 70 mA Dominant; VTXD = 0V
Standby Current IDDS 5 15 µA Includes IIO
CANH, CANL Recessive Bus Output Voltage VO(R) 2.0 2.5 3.0 V VTXD = VDDA
CANH, CANL Bus Output Voltage in Standby VO(S) -0.1 0.0 +0.1 V STBY = VTXD = VDDA; No load
Recessive Output Current IO(R) -5 +5 mA -24V < VCAN < +24V
CANH: Dominant Output Voltage VO(D) 2.75 3.5 4.5 V TXD =0; RL = 50 to 65Ω
CANL: Dominant Output Voltage VO(D) 0.5 1.5 2.25 V RL = 50 to 65Ω
Dominant: Differential Output Voltage VO(DIFF) 1.5 2.0 3.0 V TXD = VSS; RL =50 to 65Ω
Recessive: Differential Output Voltage -120 0 12 mV TXD = VDDA; RL =50 to 65Ω
-500 0 50 mV TXD = VDDA; No load
CANH: Short-Circuit Output Current IO(SC) -120 85 mA VTXD = VSS; VCANH = 0V; CANL: floating
CANL: Short-Circuit Output Current 75 120 mA VTXD = VSS; VCANL = 18V; CANH: floating
Recessive Differential Input Voltage VDIFF(R)(I) -1.0 +0.5 V Normal mode; -12V < V(CANH, CANL) < +12V
-1.0 +0.4 V Standby mode; -12V < V(CANH, CANL) < +12V
Dominant Differential Input Voltage VDIFF(D)(I) 0.9 5.0 V Normal mode; -12V < V(CANH, CANL) < +12V
1.0 5.0 V Standby mode; -12V < V(CANH, CANL) < +12V

Other components

IMU (Inertial Measurement Unit)

  • Bosch Sensortec BMI160
  • SPI Interface connected to SPI1 (MISO1, MOSI1, SCK1)
  • Chip Select: SEN_CS (connected to SN74LVC138 Y2)
  • Can wake nRF52 MCU on movement (SEN_INT1)

  • 16 bit digital, triaxial accelerometer and triaxial gyroscope

  • Very low power consumption: typically 925 μA with accelerometer and gyroscope in full operation
  • Allocatable FIFO buffer of 1024 bytes (capable of handling external sensor data)
  • Hardware sensor time-stamps for accurate sensor data fusion
  • Integrated interrupts for enhanced autonomous motion detection

PMIC

  • Texas Instruments bq24195
  • I2C interface (Wire1 address 0x6B)
  • Can interrupt nRF52 MCU on charge status and fault

  • Handles switching between USB, VIN, and battery power

  • LiPo battery charger
  • Charge safety timer, thermal regulation, and thermal shutdown
  • Optional connection for battery thermistor

Fuel Gauge

  • MAX17043
  • I2C interface (Wire1 address 0x36)
  • Can interrupt nRF52 MCU on low battery

  • Fuel-gauge system for single cell lithium-ion (Li+) batteries

  • Precision voltage measurement ±12.5mV Accuracy to 5V
  • Accurate relative capacity (RSOC) Ccalculated from ModelGauge algorithm
  • No offset accumulation on measurement
  • No full-to-empty battery relearning necessary

RTC/Watchdog

  • Ambiq Micro AM18X5 Real-Time Clock with Power Management
  • 55 nA power consumption
  • Crystal oscillator
  • I2C interface (Wire1 address 0x68)
  • Can wake MCU from hibernate (SLEEP_MODE_DEEP) at a specific time using RTC_INT.
  • Programmable hardware watchdog
  • RTC powered by XC6504 ultra-low consumption regulator so the main TPS62291 can be shut down from RTC

Wi-Fi Geolocation

The Wi-Fi module is intended for Wi-Fi geolocation only. It cannot be used as a network interface instead of using cellular. An external service provider such as the Google Geolocation Service is required for mapping Wi-Fi networks to a location.

  • ESP32-D2WD
  • SPI Interface
  • Connected to SPI1 (MISO1, MOSI1, SCK1)
  • Chip Select: WIFI_CS (connected to SN74LVC138 Y3)
  • Interrupt: ESP32 IO4 is connected to MCP23517T I/0 Expander GPA4.

The SoM connector has several pins dedicated to Wi-Fi:

# Pin Function Connected To Description
11 WIFI_EN IO WIFI & IOEX ESP32 enable. Can be controlled by this pin or software.
12 WIFI_BOOT IO WIFI & IOEX ESP32 boot mode. Can be controlled by this pin or software.
13 WIFI_TXD OUT WIFI ESP32 serial TX
14 WIFI_RXD IN WIFI ESP32 serial TX

The WIFI_EN pin turns on the Wi-Fi module. LOW=Off, HIGH=On. The default is off (with a 100K weak pull-down). It can be turned on from Pin 11 on the SoM connection, or in software from the MCP23S17 I/0 Expander 0.3.

The WIFI_BOOT pin enables programming mode.

3.3V Regulator

  • Texas Instruments TPS62291
  • 1.0A at 3.3V
  • Powers nRF52840 MCU and ESP32 Wi-Fi module
  • Can be used by your base board to power 3.3V components
  • 3.3V supply can be powered down from the RTC/Watchdog

Radio specifications

nRF52840

  • Bluetooth® 5, 2.4 GHz
    • 95 dBm sensitivity in 1 Mbps Bluetooth® low energy mode
    • 103 dBm sensitivity in 125 kbps Bluetooth® low energy mode (long range)
    • 20 to +8 dBm TX power, configurable in 4 dB steps

4G LTE cellular characteristics for EG91-EX

Parameter Value
Protocol stack 3GPP Release 13
RAT LTE Cat 1
LTE FDD Bands Band 28 (700 MHz)
Band 20 (800 MHz)
Band 8 (900 MHz)
Band 3 (1800 MHz)
Band 1 (2100 MHz)
Band 7 (2600 MHz)
WCDMA Bands Band 8 (900 MHz)
Band 1 (2100)
GSM Bands EGSM900 (900 MHz)
DCS1800 (1800 MHz)
Power class Class 4 (33dBm ± 2dB) for EGSM900
Class 1 (30dBm ± 2dB) for DCS1800
Class E2 (27dBm ± 3dB) for EGSM900 8-PSK
Class E2 (26dBm ± 3dB) for DCS1800 8-PSK
Class 3 (24dBm ± 3dB) for WCDMA bands
Class 3 (23dBm ± 2dB) for LTE FDD bands

4G LTE cellular characteristics for BG96-NA

Parameter Value
Protocol stack 3GPP Release 13
RAT LTE Cat M1
EGPRS
LTE FDD Bands Band 12 (700 MHz)
Band 13 (700 MHz)
Band 4 (1700 MHz)
Band 2 (1900 MHz)
GSM Bands EGSM850 (850 MHz)
DCS1900 (1900 MHz)

ESP32

Espressif Systems ESP32 for Wi-Fi geolocation:

Feature Description
WLAN Standards IEEE 802.11b/g/n
Antenna Port Single Antenna
Frequency Band 2412 to 2484 MHz

I/O Characteristics

These specifications are based on the nRF52840 datasheet.

Symbol Parameter Min Typ Max Unit
VIH Input high voltage 0.7 xVDD VDD V
VIL Input low voltage VSS 0.3 xVDD V
VOH,SD Output high voltage, standard drive, 0.5 mA, VDD ≥1.7 VDD - 0.4 VDD V
VOH,HDH Output high voltage, high drive, 5 mA, VDD >= 2.7 V VDD - 0.4 VDD V
VOH,HDL Output high voltage, high drive, 3 mA, VDD >= 1.7 V VDD - 0.4 VDD V
VOL,SD Output low voltage, standard drive, 0.5 mA, VDD ≥1.7 VSS VSS + 0.4 V
VOL,HDH Output low voltage, high drive, 5 mA, VDD >= 2.7 V VSS VSS + 0.4 V
VOL,HDL Output low voltage, high drive,3 mA, VDD >= 1.7 V VSS VSS + 0.4 V
IOL,SD Current at VSS+0.4 V, output set low, standard drive, VDD≥1.7 1 2 4 mA
IOL,HDH Current at VSS+0.4 V, output set low, high drive, VDD >= 2.7V 6 10 15 mA
IOL,HDL Current at VSS+0.4 V, output set low, high drive, VDD >= 1.7V 3 mA
IOH,SD Current at VDD-0.4 V, output set high, standard drive, VDD≥1.7 1 2 4 mA
IOH,HDH Current at VDD-0.4 V, output set high, high drive, VDD >= 2.7V 6 9 14 mA
IOH,HDL Current at VDD-0.4 V, output set high, high drive, VDD >= 1.7V 3 mA
tRF,15pF Rise/fall time, standard drivemode, 10-90%, 15 pF load1 9 ns
tRF,25pF Rise/fall time, standard drive mode, 10-90%, 25 pF load1 13 ns
tRF,50pF Rise/fall time, standard drive mode, 10-90%, 50 pF load1 25 ns
tHRF,15pF Rise/Fall time, high drive mode, 10-90%, 15 pF load1 4 ns
tHRF,25pF Rise/Fall time, high drive mode, 10-90%, 25 pF load1 5 ns
tHRF,50pF Rise/Fall time, high drive mode, 10-90%, 50 pF load1 8 ns
RPU Pull-up resistance 11 13 16
RPD Pull-down resistance 11 13 16
CPAD Pad capacitance 3 pF
CPAD_NFC Pad capacitance on NFC pads 4 pF
INFC_LEAK Leakage current between NFC pads when driven to different states 1 10 μA

1Rise and fall times based on simulations

Mechanical specifications

Dimensions and Weight

Parameter Value Units
Width 28 mm
Length 93 mm
Thickness 4 mm
Weight g

Weight will be provided at a later date.

Mechanical drawing

Will be provided at a later date.

Dimensions are in millimeters.

Layout Considerations

Will be provided at a later date.

Product Handling

ESD Precautions

The Tracker SoM contains highly sensitive electronic circuitry and is an Electrostatic Sensitive Device (ESD). Handling an module without proper ESD protection may destroy or damage it permanently. Proper ESD handling and packaging procedures must be applied throughout the processing, handling and operation of any application that incorporates the module. ESD precautions should be implemented on the application board where the B series is mounted. Failure to observe these precautions can result in severe damage to the module!

Connectors

The U.FL antenna connectors are not designed to be constantly plugged and unplugged. The antenna pin is static sensitive and you can destroy the radio with improper handling. A tiny dab of glue (epoxy, rubber cement, liquid tape or hot glue) on the connector can be used securely hold the plug in place.

Default settings

The AssetTracker SoM comes pre-programmed with a bootloader and a user application called Tinker. This application works with an iOS and Android app also named Tinker that allows you to very easily toggle digital pins, take analog and digital readings and drive variable PWM outputs.

The bootloader allows you to easily update the user application via several different methods, USB, OTA, Serial Y-Modem, and also internally via the Factory Reset procedure. All of these methods have multiple tools associated with them as well.

Ordering Information

SKU Description Packaging
T523 Family (Europe)
T523MEA Tracker SoM LTE CAT1/3G/2G (Europe), [x1] Each
T523MTY Tracker SoM LTE CAT1/3G/2G (Europe), Tray [x50] Tray (50)
T523MKIT Tracker SoM LTE CAT1/3G/2G (Europe) Evaluation Kit, [x1] Each
T402 Family (North America)
T402MEA Tracker SoM LTE M1 (NorAm), [x1] Each
T402MTY Tracker SoM LTE M1 (NorAm), Tray [x50] Tray (50)
T402MKIT Tracker SoM LTE M1 (NorAm) Evaluation Kit, [x1] Each

Revision history

Revision Date Author Comments
pre1 31 Mar 2020 RK Preview Release 1
pre2 12 May 2020 RK Added partial dimensions