SPI Isolator 4 Click

How does it work?

SPI Isolator 4 Click as its foundation uses the ADuM341E1BRWZ, a quad-channel digital isolator optimized for a serial peripheral interface from Analog Devices. This isolation component provides outstanding performance characteristics by combining high speed and CMOS technology and uses a high-frequency carrier to transmit data across the isolation barrier using iCoupler chip scale transformer coils separated by layers of polyimide isolation. Its data channels are independent and available in various configurations with a withstand voltage rating of 5kVrms.

Using an ON/OFF keying (OOK) technique and the differential architecture, the ADuM341E has a very low propagation delay and high speed. It operates with the external supply voltage ranging from 2.25V to 5.5V, providing compatibility with lower voltage systems enabling voltage translation functionality across the isolation barrier. The ADuM341E architecture is designed for high common-mode transient (CMTI) immunity and high immunity to electrical noise and magnetic interference.

Unlike other optocoupler alternatives, dc correctness is ensured in the absence of input logic transitions. Two different fail-safe options are available, by which the outputs go into a predetermined state when the input power supply is not applied, or the inputs are disabled.

SPI Isolator 4 Click communicates with an MCU using the SPI serial interface with a maximum data rate of 100Mbps. This Click board™ also comes with an SDO line enable control pin, labeled as EN1 routed on the PWM pin of the mikroBUS™ socket. When EN1 is in a high logic state, the SDO line is enabled, and when EN1 is in a low logic state, the SDO line is disabled to the high-Z state.

This Click board™ can operate with both 3.3V and 5V logic voltage levels selected via the VCC SEL jumper. This way, both 3.3V and 5V capable MCUs can use the SPI communication lines correctly. 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 4 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	EN1	SPI SDO Signal Enable
	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 4 Click electrical specifications

Software Support

We provide a library for the SPI Isolator 4 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 SPI Isolator 4 Click driver.

Key functions

• spiisolator4_generic_write SPI Isolator 4 data writing function.

• spiisolator4_generic_read SPI Isolator 4 data reading function.

• spiisolator4_set_enable SPI Isolator 4 enable isolator function.

Example Description

This library contains API for the SPI Isolator 4 click driver. This demo application shows an example of an SPI Isolator 4 click wired to the nvSRAM 4 click for reading Device ID.

 void application_task ( void ) 
 { 
     get_device_id( ); 
     log_printf( &logger, "  Device ID : 0x%.8LXrn", device_id );  
     log_printf( &logger, "--------------------------rn" );  
     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.SPIIsolator4

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 by a mikroSDK – Mikroe Software Development Kit. To ensure proper operation of mikroSDK compliant Click board™ demo applications, mikroSDK should be downloaded from LibStock and installed for the compiler you are using.

For more information about mikroSDK, visit the official page.