Pressure 18 Click is a compact add-on board that contains a board-mount pressure sensor. This board features the BMP384, a robust barometric pressure sensor delivering market-leading accuracy in a compact package from Bosch Sensortec. The BMP384 provides a relative accuracy of ±9Pa and typical absolute accuracy of ±50Pa with ultra-low noise, low power consumption, and a temperature coefficient offset of ±1Pa/K. It converts output data into a 24-bit digital value and sends the information via a configurable host interface that supports SPI and I2C serial communications. It measures pressure from 300hPa to 1250hPa over a wide operating temperature range. This Click board™ is suited for various pressure-based applications, altitude tracking, industrial, consumer, weather stations, and more.

Pressure 18 Click as its foundation uses the BMP384, a high accuracy, low-power, and low noise 24-bit absolute barometric pressure sensor from Bosch Sensortec. The BMP384 consists of a piezo-resistive pressure sensing element and a mixed-signal ASIC that performs A/D conversions and provides the conversion results alongside sensor-specific compensation data through a digital interface. It also provides the highest flexibility and can be adapted to the requirements regarding accuracy, measurement time, and power consumption by selecting many possible combinations of the sensor settings.

The BMP384 is very accurate, covering a wide measurement pressure range from 300hPa to 1250hPa, alongside a relative accuracy of ±9Pa (equivalent to ±75cm difference in altitude), the typical absolute accuracy of ±50Pa, and a temperature coefficient offset of ±1Pa/K. This feature makes it suitable for water-level detection and differential barometric pressure measurements.

This sensor operates in three power modes: Sleep, Normal, and Forced Mode. The Normal Mode comprises automated perpetual cycling between an active measurement period and an inactive Standby period. In Sleep Mode, no measurements are being performed, while in Forced Mode, a single measurement performs. When a measurement is finished, the BMP384 returns to Sleep Mode. Also, a set of oversampling settings are available, ranging from ultra-low power to highest resolution setting to adapt the Click board™ to the target application.

Pressure 18 Click allows using both I2C and SPI interfaces with a maximum frequency of 3.4MHz for I2C and 10MHz for SPI communication. The selection can be made by positioning SMD jumpers labeled as COMM SEL in an appropriate position. Note that all the jumpers' positions must be on the same side, or the Click board™ may become unresponsive. While the I2C interface is selected, the BMP384 allows choosing the least significant bit (LSB) of its I2C peripheral address using the SMD jumper labeled ADDR SEL. This Click board™ also possesses an additional interrupt pin, routed to the INT pin on the mikroBUS™ socket, indicating when a specific interrupt event occurs, such as FIFO overflow, data-ready, and more.

This Click board™ can be operated only with a 3.3V logic voltage level. The board must perform appropriate logic voltage level conversion before using MCUs with different logic levels. However, the Click board™ comes equipped with a library containing functions and an example code that can be used, as a reference, for further development.

• Interface: I²C, SPI
• Compatibility: mikroBUS™
• Dimensions: 28.6 x 25.4mm
• Input Voltage: 3.3V
• Supply Voltage: 3.3V
• Pressure Measurement Range: Min. 300 hPa, Max. 1250 hPa
• Relative Pressure Accuracy: ±9 Pa
• Absolute Pressure Accuracy: ±50 Pa
• Resolution: 24 bit
• Operating Temperature Range: Min. -40°C, Typ. +25°C, Max. +85°C

• Schematic
• BMP384 Datasheet
• mikroSDK
• LibStock