Hall Current 21 Click

How does it work?

Hall Current 21 Click is based on the ACS37030, a DC to 5MHz bandwidth, a galvanically-isolated current sensor from Allegro Microsystems, designed to provide precise current measurements across a wide frequency range, ideal for applications requiring fast and accurate current monitoring. The ACS37030 offers bidirectional current sensing, with a range of ±65A and a sensitivity of 20.3mV/A, allowing for precise monitoring of both positive and negative currents. It is AEC-Q100 Grade 0 qualified, ensuring high reliability and robustness, even in harsh environments. Additionally, its wide operating bandwidth and low noise make it suitable for fast control loops and monitoring high-speed switching currents. This Click board™ is ideal for various applications, including power supplies for servers and data centers, solar DC-DC converters, and other high-performance power management systems that demand fast, accurate, and isolated current sensing.

The ACS37030 uses two distinct signal paths for current sensing: a Hall-effect element that captures DC and low-frequency currents and an inductive coil that measures high-frequency currents. Combining the outputs of both paths, this sensor achieves broad frequency coverage with minimal noise, ensuring reliable performance in various operating conditions. As the frequency increases, the coil’s properties enhance the signal-to-noise ratio (SNR), further reducing noise at the output and ensuring clean and accurate measurements.

The sensor’s innovative design provides a high level of isolation. The magnetic coupling between the current flow in the conductor and the sensor elements ensures that the current is sensed without direct physical contact, allowing for an isolation rating of 3500 VRMS between the primary and secondary signal leads. This rating provides a working voltage of up to 840VRMS, making it suitable for applications requiring high isolation, such as industrial and automotive environments.

The ACS37030 outputs an analog signal that varies linearly with the bidirectional AC or DC primary current within the range specified. Then, it sends its analog output to the ADC122S101, a two-channel 12-bit A/D converter from Texas Instruments that uses a standard 4-Wire SPI serial interface to communicate with the host MCU. This ADC is based on a successive/approximation register architecture with an internal track-an-hold circuit and fully specified over a sample rate range of 500ksps to 1Msps.

This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the communication lines properly. Also, this 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.

Specifications

Pinout diagram

This table shows how the pinout on Hall Current 21 Click corresponds to the pinout on the mikroBUS™ socket (the latter shown in the two middle columns).

Notes	Pin					Pin	Notes
	NC	1	AN	PWM	16	NC
ID SEL	RST	2	RST	INT	15	NC
SPI Select / ID COMM	CS	3	CS	RX	14	NC
SPI Clock	SCK	4	SCK	TX	13	NC
SPI Data OUT	SDO	5	MISO	SCL	12	NC
SPI Data IN	SDI	6	MOSI	SDA	11	NC
Power Supply	3.3V	7	3.3V	5V	10	5V	Power Supply
Ground	GND	8	GND	GND	9	GND	Ground

Onboard settings and indicators

Hall Current 21 Click electrical specifications

Software Support

We provide a library for the Hall Current 21 Click as well as a demo application (example), developed using MIKROE compilers. The demo can run on all the main MIKROE development boards.

Package can be downloaded/installed directly from NECTO Studio Package Manager (recommended), downloaded from our LibStock™ or found on MIKROE github account.

Library Description

This library contains API for Hall Current 21 Click driver.

Key functions

• hallcurrent21_read_voltage_avg This function reads a desired number of ADC samples and calculates the average voltage level of the selected input channel.

• hallcurrent21_calib_resolution This function reads the sensor voltage reference and calibrates the data resolution at a known load current.

• hallcurrent21_read_current This function reads the input current level [A].

Example Description

This example demonstrates the use of Hall Current 21 Click by reading and displaying the input current measurements.

void application_task ( void ) 
 { 
     float current = 0; 
     if ( HALLCURRENT21_OK == hallcurrent21_read_current ( &hallcurrent21, &current ) )  
     { 
         log_printf( &logger, " Current : %.1f Arnn", current ); 
         Delay_ms ( 1000 ); 
     } 
 }

The full application code, and ready to use projects can be installed directly from NECTO Studio Package Manager (recommended), downloaded from our LibStock™ or found on MIKROE github account.

Other MIKROE Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.HallCurrent21

Additional notes and informations

Depending on the development board you are using, you may need USB UART click, USB UART 2 Click or RS232 Click to connect to your PC, for development systems with no UART to USB interface available on the board. UART terminal is available in all MIKROE compilers.

mikroSDK

This Click board™ is supported with mikroSDK – MIKROE Software Development Kit. To ensure proper operation of mikroSDK compliant Click board™ demo applications, mikroSDK should be downloaded from the LibStock and installed for the compiler you are using.

For more information about mikroSDK, visit the official page.