ISO ADC 5 Click

How does it work?

ISO ADC 5 Click as its foundation uses the MAX22530, a 12-bit, 4-channel ADC with a 5kVRMS isolated SPI interface from Maxim Integrated. The ADC and all field-side circuits are powered by an integrated, isolated DC-DC converter that can verify field-side functionality even when there is no input signal or other field-side supply. It continually digitizes the input voltage on the field-side of an isolation barrier, and it transmits the data across the isolation barrier to the logic-side of the devices, where the magnitude of the input voltage is compared to programmable thresholds.

The MAX22530 ADC employs a 12-bit SAR architecture with a nominal sampling rate of 20ksps per channel and has an input voltage of up to 1.8V. Placed voltage dividers make the proper ADC input voltage on the input analog channels, which, based on the input in the range from 0 to 48V, gives the required input to the ADC in its range from 0 to 1.8V. After Power-Up, the ADC runs continually at the nominal sampling rate. The MAX22530 also features a precision internal voltage reference of 1.8V with a maximum error of ±2% over the entire operating temperature range.

The MAX22530 communicates with MCU using the standard SPI serial interface with a maximum frequency of 10MHz. Besides, it continuously monitors multiple possible fault conditions such as ADC functionality error, SPI framing error, CRC errors from SPI communications, and internal isolated data stream loss. This hardware alert feature is provided through the interrupt pin, routed on the CS pin of the mikroBUS™ socket, which asserts low when an enabled fault is detected.

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 SPI 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.

Specifications

Pinout diagram

This table shows how the pinout on ISO ADC 5 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
	NC	2	RST	INT	15	INT	Interrupt
SPI Chip Select	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

ISO ADC 5 Click electrical specifications

Software Support

We provide a library for the ISO ADC 5 Click as well as a demo application (example), developed using MikroElektronika compilers. The demo can run on all the main MikroElektronika development boards.

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

Library Description

This library contains API for ISO ADC5 Click driver.

Key functions:

• isoadc5_cfg_setup – Config Object Initialization function.
• isoadc5_init – Initialization function.

Examples description

This example demonstrates the use of ISO ADC 5 click board.

The demo application is composed of two sections :

void application_task ( void )
{
    float v_ain1 = 0, v_ain2 = 0, v_ain3 = 0, v_ain4 = 0;
    err_t error_flag = isoadc5_read_voltage( &isoadc5, ISOADC5_ADC_FILTERED, ISOADC5_ADC_CHANNEL_1, &v_ain1 );
    error_flag |= isoadc5_read_voltage( &isoadc5, ISOADC5_ADC_FILTERED, ISOADC5_ADC_CHANNEL_2, &v_ain2 );
    error_flag |= isoadc5_read_voltage( &isoadc5, ISOADC5_ADC_FILTERED, ISOADC5_ADC_CHANNEL_3, &v_ain3 );
    error_flag |= isoadc5_read_voltage( &isoadc5, ISOADC5_ADC_FILTERED, ISOADC5_ADC_CHANNEL_4, &v_ain4 );
    
    if ( ISOADC5_OK == error_flag )
    {
        log_printf( &logger, " AIN 1 voltage: %.3f Vrn", v_ain1 );
        log_printf( &logger, " AIN 2 voltage: %.3f Vrn", v_ain2 );
        log_printf( &logger, " AIN 3 voltage: %.3f Vrn", v_ain3 );
        log_printf( &logger, " AIN 4 voltage: %.3f Vrnrn", v_ain4 );
        Delay_ms( 1000 );
    }
}

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

Other mikroE Libraries used in the example:

• MikroSDK.Board
• MikroSDK.Log
• Click.ISOADC5

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. The terminal available in all MikroElektronika compilers, or any other terminal application of your choice, can be used to read the message.

mikroSDK

This Click board™ is supported with mikroSDK – MikroElektronika 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.