Monitor One datasheet

The pictures in this preliminary datasheet are of a pre-release unit. The production units will be a different color, and may have other minor differences.

The Monitor One is an off-the-shelf complete gateway design, like the Tracker One. The Monitor One is in a larger IP67 waterproof enclosure with room inside for an expansion card and additional connectors, allowing it to be used in more custom scenarios than the Tracker One.

• Ready to go with rugged IP67-rated enclosure with room inside for an expansion card.
• Flexible power supply to easily add asset tracking to most devices with a 6 - 30 VDC power input and a large 18650 LiPo battery pack.
• Internal or external antennas for cellular and GNSS.
• Temperature sensors on the carrier board, and also a battery pack temperature sensor.
• Expansion card connector to allow for custom application specific hardware.
• RGB LED for system status, and two user RGB LEDs for your own use, visible from outside the enclosure.
• User button, waterproof and accessible from outside the enclosure.

Particle gateway device like the Monitor One and Tracker One are designed to be used off-the-shelf to interface to other devices and sensors using standard protocols such as CAN bus, I2C, and serial.

For information on setting up a Monitor One Developer Edition, see the Monitor One Quickstart.

Block diagram

Details about the Tracker SoM that is contained within the Monitor One can be found in the Tracker SoM Datasheet.

Certification

External features

User button

A waterproof button is available from the outside of the enclosure.

• Long press (10 seconds) resets the device (as if the RESET button was pressed)
• Shorter press and multiple press can be handled by your user firmware for your own features

User LEDs (2)

• There are two small RGB LEDs visible from the outside on the side of the unit, next to the user button.
• The upper LED defaults to being a GNSS lock indicator:
  • Off: GNSS off
  • Blinking (green): attempting to get a GNSS fix
  • On (green): GNSS fix acquired
• You can program custom colors, blinking, and fade effects from your user firmware for the lower LED.
• LEDs are controlled by a ADP8866 I2C LED controller.

Connectors

The bottom plate of the Monitor One can be customized with different connectors for your application.

By default the Monitor One uses the internal cellular and GNSS antennas, but can be switched to using the external connectors inside the enclosure.

The cellular (1) and GNSS (4) antennas are not connected internally at the factory. In order to use the external connectors you must open the case, disconnect the internal antenna, and instead connect the U.FL connector for the external jack.

The Monitor One is equipped with 2 external-facing SMA bulkhead connectors for both cellular and GNSS but are disconnected internally. The hardware is ready for use with external antennas giving the ability to connect a wide variety of application-specific antennas. It is recommended that the user perform required RF certifications with the selected antenna installed as the Monitor One has only been certified for use in select regions with the internal antennas.

Mounting

The Monitor One is intended to be mounted in the orientation shown at the top of the page, with the connectors facing down. You can also mount it with the mounting plate mounted on a flat surface as the GNSS antenna is angled to allow it to work in either orientation.

When using external cellular and GNSS antennas you can orient the Monitor One in other directions.

The mounting plate contains two magnets (3) that allow it to be easily mounted on a metal surface.

The mounting plate is removable from the back of the unit after removing the screw on the bottom (4), near the expansion connectors.

Once removed, you can screw or bolt the mounting plate through the four holes (1) and reattach the Monitor One. This is good for rough conditions and for mounting on non-metal surfaces.

The mounting plate can be strap mounted through the two slots (2).

The magnets do not need to removed to use screw, bolt, or strap mounting.

When mounting using a strap, the strap will hold the mounting bracket against a surface and is sandwiched between the mounting bracket and the Monitor One enclosure.

If you wish to fabricate your own compatible mounting bracket, the STEP file can found in the Monitor One Github repository.

Internal features

I/O Card

The Monitor One is designed with easy-to-use expansion headers and an enclosure with sufficient space inside for an expansion card, and for additional expansion connector through the wall of enclosure.

The Monitor One Developer's Edition includes the I/O Card, which includes:

I/O Card M12 8-pin to flying leads

The Monitor One includes a M12 8-pin male to flying leads cable, 1500±20mm (about 60 inches or 5 feet). This is used to power the Monitor One, and also use the 4-20mA, 0-10V analog in, CAN bus, and RS485 (Modbus) interfaces.

Looking at the pins on the end of the connector on the cable

Also included is an adapter from screw terminals to a 5.5x2.1mm barrel jack, center positive. If you disconnect and reconnect the adapter, make sure the + screw terminal is connected to red and the - screw terminal is connected to black. An appropriate 24 VDC power adapter is included.

Any 6VDC to 30VDC power adapter at 2A with a 5.5x2.1mm barrel connector, center positive can be used instead, if desired. For automotive use, you can use this power input directly to a 12V or 24V vehicle power system as the power supply is designed to handle transient voltage present on vehicle power systems.

The RS485 and CAN interface pins on the M12 8-pin connector cannot be used as GPIO.

I/O Card M12 4-pin to flying leads

The Monitor One includes a M12 4-pin male to flying leads cable, 1500±20mm (about 60 inches or 5 feet).

I/O Card details

The M12 4-pin bulkhead connector has flying leads that are connected to the screw terminals (18) as follows:

Customizing the I/O Card

If you wish to build upon the I/O Card, there is a small prototyping area (1).

If you need signals from the expansion card interface, they are available in the rows of pins (19, 20).

If you wish to disable an interface that you are not using and re-use the pins on the M12 8-pin connector, there is a small trace jumper between the rows of pins in area (14). Cutting this trace isolates the expansion card signal from the signal to the connector (16). Then you can solder a small jumper wire to replace the signal on the M12 8-pin.

The Eagle CAD schematic and board layout files for the I/O card can be found in the Monitor One Github repository.

Block diagram - I/O Card

Schematics - I/O Card

Interconnects - I/O Card

RS485 - I/O Card

CAN - I/O Card

4-20mA - I/O Card

0-10V - I/O Card

Slow signal input - I/O Card

Relay - I/O Card

EEPROM - I/O Card

Board layout - I/O Card

Prototype Card

B8B-PH connector

The left connector (7) attaches to the M12 8-pin connector with a short adapter cable. You don't have to use this cable setup, but it's often convenient to do so.

• Connector: JST B8B-PH (right angle)
• Mates with: JST PHR-8

• We recommend that you keep pin 8 (VIN) and pin 7 (GND) is the same positions.
• Other pins can be used as desired.
• The pins on the board layout are numbered 8 - 1 left to right, opposite of how the pins on the cable are numbered.

Screw terminals

• The order of these pins isn't significant, but this is how the I/O Card is wired, so it probably best to be consistent.

Schematics - Prototyping Card

The Eagle CAD schematic and board layout files for the prototype can be found in the Monitor One Github repository.

Expansion card interface

• Expansion card size: 50mm x 90mm (approximately 2" x 3.5")
• Connectors: 24-pin 0.1" headers (two, one on each long side)
• Male header pins on the bottom of expansion card
• Attachment: 4 screws to standoffs (M3 screw recommended)

Pre-built expansion cards will be available, including the Prototype Card. You can also design and fabricate your own.

If you are building your own card, you can start with the design for the I/O card or prototype card. The Eagle CAD schematic and board layout files can be found in Monitor One Github repository.

Expansion card pinout

Expansion card dimensions

Expansion card location

The enclosure typically has a panel-mount M12 8 pin female connector in location 17 in the picture above. This is connected via a short cable to a PHR-8 female connector that attaches to your expansion card. The picture above shows the cable but a board is not installed in the picture.

The functions of the pins on the M12 8-pin connector are dependent on your base board, but the following pinouts are recommended:

• Cable length: 60 ±5 mm
• Wire gauge: 24 AWG
• M12 8-pin connector, A-coded

M12 connectors

The standard M12 connectors are IP67 waterproof (connected or not), 12 mm in diameter, and have 8 pins or 4 pins. However, M12 connectors are available from 2 pin to 17 pins. The connectors with smaller numbers of pins often have higher voltage and current ratings.

The panel-mount 8-pin connector on the Monitor One is female, with the following pinout:

Looking at the bulkhead connector from outside the enclosure

The panel mount M12 8-pin connector fits in the following hole in the enclosure:

GPIO

• On the Monitor One, pins A0 and A1 are used in I2C mode by the user RGB LED temperature sensor. Pins A0 and A1 cannot be used as GPIO.
• On the Monitor One, you should not use A2 and A3 as GPIO or analog inputs as they are used by the external user button and battery temperature thermistor.
• All GPIO are 3.3V and are not 5V tolerant.

When using the I/O Card:

ADC

• On the Monitor One, you should not use A2 and A3 as analog inputs as they are used by the external user button and battery temperature thermistor.

SPI

• Any available GPIO can be used as a SPI CS/SS pin.

I2C

• On the Monitor One, pins A0 and A1 are used in I2C mode by the user RGB LED and temperature sensor. Pins A0 and A1 cannot be used as GPIO.
• On the Monitor One (and Tracker SoM), Wire and Wire3 are two different I2C peripherals and can be used at the same time.
• On the Monitor One (and Tracker SoM), Wire3 and Serial1 share the same pins and only one can be used at a time.
• I2C is 3.3V only and is not 5V tolerant.
• There are 4.7K pull-up resistors on TSOM_A0_SDA and TSOM_A1_SCL to 3.3V on the base board.

Serial (UART)

• On the Monitor One (and Tracker SoM), Wire3 and Serial1 share the same pins and only one can be used at a time.
• Hardware flow control is not available on the Monitor One.
• Serial pins are 3.3V only and are not 5V tolerant.
• Additional interface chips are required for other serial standards such as RS232 and RS485.

PWM

• On the Monitor One, you should not use A2 and A3 as PWM outputs as they are used by the external user button and battery temperature thermistor.
• All pins on the same hardware timer (PWM0, PWM1, or PWM2) must share the same frequency but can have different duty cycles.

CAN

The CAN transceiver is included on the Tracker SoM. However if you implement CAN on your expansion card, you will probably want to add protection circuitry. This circuit is present on the Monitor One CAN expansion card and also on the Tracker One.

Note that the two 60.4 ohm resistors are DNP (do not populate). If populated, these provide the 120 ohm CAN termination, if you need it in your design.

All expansion card pins

• Pins 9 and 10 have NFC in the name from the Tracker SoM, however NFC cannot be used on the Monitor One as the pins must be used as VIN_EN and PERIPH_INT.

I/O characteristics

The GPIO pins on the expansion connector have the following specifications, from the nRF52840 datasheet:

• GPIO default to standard drive (2mA) but can be reconfigured to high drive (9mA) in Device OS 2.0.0 and later using the pinSetDriveStrength() function.

GPIO and port leakage current warning

Be careful when you are connecting GPIO or ports such as serial that may have power when the Monitor One is not powered, such as when using shipping mode.

If you have current flowing into GPIO or ports of the nRF52840 when it is powered down, it can cause it to enter a state where it cannot be reawaked without removing all power from it, including the internal LiPo battery. This may be difficult if you've sealed your Monitor One enclosure.

The Tracker One has a TI TS3A5018 Quad SPDT Analog Switch on the three GPIO pins (A3, D9/RX/SDA, D8/TX/SCL) to prevent this. The switch is normally open, and is closed when the CAN_5V is powered. By default, Tracker Edge enables CAN_5V when in normal operating mode and turns it off during sleep, however this behavior can be changed by using enableIoCanPower() and enableIoCanPowerSleep() in the TrackerConfiguration object.

The Tracker One circuit looks like this, and you may want to implement something similar if you are in a scenario where you have externally powered peripherals.

This is not necessary if your external peripherals are powered by 3V3 or CAN_5V.

VIN disable

By default, if power is applied at the VIN pin it will be used to power the Monitor One and charge the built-in battery.

If you are supplying VIN from another, larger battery pack, and want to be able to disconnect the VIN power supply to minimize current loss, you can do so using the following circuit in lieu of using NFC2 as the relay pin, as the I/O Card does.

By disconnecting the VIN power supply, it reduces the current used by the VIN and PMIC voltage regulators. The Monitor One can still be powered by its internal LiPo battery. This is particularly advantageous if the Monitor One is in sleep mode while VIN is disconnected as the power supply loss will be large compared to the very low sleep current in this scenario.

GPIO and Ports vs. Tracker One

¹Available on expansion card connector (internal)

• On the Monitor One, the expansion card connector allows the use the I2C, Serial, and SPI at the same time
• On the Tracker One, you must choose between using the M8 for either serial or I2C. SPI is not available.

Tracker feature comparison

¹On the Tracker One, the M8 can be configured for GPIO, I2C (SDA and SCL), or Serial (RX and TX) on two pins.

²Both internal and external GNSS and cellular are supported by physically changing the antenna connector inside the enclosure.

³There is no external MCU USB connector on the Monitor One.

⁴The Monitor One uses the Tracker SoM BLE chip antenna on the board and does not include a separate BLE antenna, but one could be added using the BLE U.FL connector.

⁵The Tracker M uses a shared antenna for BLE and Wi-Fi geolocation. You can use the built-in trace antenna or an external 2.4 GHz/5 GHz dual-band antenna, selectable in software.

⁶A small portion of the flash file system is used by the system, and a configurable portion can be used for store and forward, to optionally allow location publishes to be saved when the device is offline to be uploaded later. The remainder of the flash file system can be used by user applications.

Schematics

Mechanical specifications

Operating temperature

Dimensions and weight

Dimensions for top cover artwork

Power consumption

To be provided at a later date.

Battery specifications

• Lithium-ion cylindrical rechargeable battery
• Model: 18650-4P
• Description: Single cell with PCM
• Battery capacity: 12200 mAh
• Batter voltage : 3.7 VDC (nominal)
• Manufacturer: Guangdong Zhaoeng Technology Co., Ltd. (Guangdong, China)
• Datasheet

Country compatibility

To be provided at a later date.

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Ordering information

To be provided at a later date.

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Certification

To be provided at a later date.

Product handling

ESD precautions

The Monitor One 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!

Battery warning

CAUTION

RISK OF EXPLOSION IF BATTERY IS REPLACED BY AN INCORRECT TYPE. DISPOSE OF USED BATTERIES ACCORDING TO THE INSTRUCTIONS.

Disposal

This device must be treated as Waste Electrical & Electronic Equipment (WEEE) when disposed of.

Any WEEE marked waste products must not be mixed with general household waste, but kept separate for the treatment, recovery and recycling of the materials used. For proper treatment, recovery and recycling; please take all WEEE marked waste to your Local Authority Civic waste site, where it will be accepted free of charge. If all consumers dispose of Waste Electrical & Electronic Equipment correctly, they will be helping to save valuable resources and preventing any potential negative effects upon human health and the environment of any hazardous materials that the waste may contain.

Revision history