SPI Isolator Click

How does it work?

SPI Isolator Click is based on the ADuM4154, a 5kV digital isolator from Analog Devices designed to enhance the serial peripheral interface (SPI) performance. It incorporates iCoupler® technology for chip scale transformer, ensuring minimal delay and jitter on the SPI bus signals like SCLK, SI, SO, and SSS. Additionally, it features a slave-select multiplexing mechanism that can accommodate up to four slave devices through a single isolator. This design enables precise timing control by ensuring the slave select signal reaches the intended slave device with minimal delay when activated. The board is ideal for applications requiring SPI-bus isolation, including industrial automation systems, sensor isolation, and various other uses.

SPI Isolator Click communicates with an MCU using the SPI serial interface with a maximum clock frequency of 17MHz. The isolated lines are provided on an onboard screw terminals. You can distinguish the power VCC and GND lines from the data lines, which are SCLK, SO, SI, and SSS. The isolator can work with external supply voltages from 3V up to 5.5V.

This Click board™ can operate with either 3.3V or 5V logic voltage levels selected via the VCC SEL switch. This way, both 3.3V and 5V capable MCUs can 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.

Specifications

Pinout diagram

This table shows how the pinout on SPI Isolator 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	NC
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

SPI Isolator Click electrical specifications

Software Support

We provide a library for the SPI Isolator 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), downloaded from our LibStock™ or found on Mikroe github account.

Library Description

This library contains API for SPI Isolator Click driver.

Key functions

• Generic transfer function.

• Write the byte of data function.

• Read the byte of data function.

Example Description

TThe click is designed to run on either 3.3V or 5V power supply. It communicates with the target microcontroller over SPI interface. In this example we have used an 8×8 click board connected to a SPI Isolator click board.

 void application_task ( void ) 
 { 
     log_info( &logger, "> Display Character ..." ); 
     c8x8_display_byte( &spiisolator, demo_char ); 
     Delay_ms ( 1000 ); 

     log_info( &logger, "> Display String ..." ); 
     c8x8_display_string( &spiisolator, &demo_string[ 0 ] ); 
     Delay_ms ( 1000 ); 

     log_info( &logger, "> Display Image ON ..." ); 
     c8x8_display_image( &spiisolator, &demo_img_on[ 0 ] ); 
     Delay_ms ( 500 ); 

     log_info( &logger, "> Display Image OFF ..." ); 
     c8x8_display_image( &spiisolator, &demo_img_off[ 0 ] ); 
     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.Spiisolator

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.