Hall Current 14 Click is a compact add-on board that contains a precise solution for AC/DC current sensing. This board features the MCS1801, a fully integrated Hall-effect-based isolated linear current sensor designed for the current range of ±25A from Monolithic Power Systems (MPS). The galvanic isolation between the pins of the primary copper conductive path and the sensor leads allows the MCS1801 to replace optoisolators or other isolation devices. Applied current flowing through this copper conduction path generates a magnetic field that the differential Hall sensors convert into a proportional voltage, where after that, the user is given the option to process the output voltage as an analog or digital value. This Click board™ is ideal for applications requiring a combination of high-current monitoring and high isolation voltage between the primary high-current and low-voltage sides.

Hall Current 14 Click as its foundation uses the MCS1801, a Hall-effect current sensor that sends an analog voltage proportional to the magnetic field intensity caused by the current flowing through the primary input conductor from Monolithic Power Systems (MPS). Immune to external magnetic fields by differential sensing, the MCS1801 can detect both DC and AC designed for the current range of ±25A. Device accuracy, ±3%, is optimized across the operating ambient temperature through the close proximity of the magnetic signal to the Hall sensors.

A primary conductor with a low resistance allows current to flow close to the IC, containing high-accuracy Hall-effect sensors. This current generates a magnetic field sensed at two different points by the integrated Hall-effect transducers. The magnetic field difference between these two points is then converted into a voltage (analog output) proportional to the applied current.

The analog output signal of the MCS1801 can be converted to a digital value using MCP3221, a successive approximation A/D converter with a 12-bit resolution from Microchip using a 2-wire I2C compatible interface, or can be sent directly to an analog pin of the mikroBUS™ socket labeled as AN. Selection can be performed by onboard SMD jumper labeled as AD SEL to an appropriate position marked as AN and ADC.

The MCP3221 provides one single-ended input with low power consumption, a low maximum conversion current, and a Standby current of 250μA and 1μA, respectively. Data can be transferred at rates of up to 100kbit/s in the Standard and 400kbit/s in the Fast Mode. Also, maximum sample rates of 22.3kSPS with the MCP3221 are possible in a Continuous-Conversion Mode with a clock rate of 400kHz.

Also, this Click board™ should be connected in series with the load. The current is measured by two onboard terminal connectors, one terminal block for the positive and the other for the negative current input.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, it is allowed for both 3.3V and 5V capable MCUs to use the communication lines properly. However, the Click board™ comes equipped with a library containing easy-to-use functions and an example code that can be used, as a reference, for further development.

• Interface: Analog, I²C
• Compatibility: mikroBUS™
• Dimensions: 57.15 x 25.4mm
• Input Voltage: 3.3V or 5V
• Supply Voltage: Min. 3.3V, Max. 5V
• Measurement Range: Min. -25A, Max. +25A
• Sensitivity: 80 mV/A
• Isolation Working Voltage: 200 VRMS
• Operating Temperature Range: Min. -40°C, Typ. +25°C, Max. +120°C

• Schematic
• MCP3221 Datasheet
• MCS1801 Datasheet
• mikroSDK
• LibStock