How Does The SPI Isolator 4 Click Board™Work?
The SPI Isolator 4 Click Board™ is based on 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.
The SPI Isolator 4 Click Board™ communicates with 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, labelled 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.
The SPI Isolator 4 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
| Type | Isolators,SPI |
| Applications | Can be used for general SPI-bus isolation, RS485 and CAN FG industrial field bus isolation, GPIO multichannel isolation, and many more |
| On-board modules | ADuM341E - quad-channel digital isolator optimized for a serial peripheral interface from Analog Devices |
| Key Features | High common-mode transient immunity, high performance, low propagation delay, 100Mbps maximum guaranteed data rate, safety and regulatory approvals, low power consumption, and more |
| Interface | SPI |
| Compatibility | mikroBUS |
| Click board size | M (42.9 x 25.4 mm) |
| Input Voltage | 3.3V or 5V,External |
PINOUT DIAGRAM
This table shows how the pinout of the SPI Isolator 4 Click Board™ 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
| Label | Name | Default | Description |
|---|---|---|---|
| LD1 | PWR | - | Power LED Indicator |
| JP1 | VCC SEL | Left | Logic Level Voltage Selection 3V3/5V: Left position 3V3, Right position 5V |
SPI ISOLATOR 4 CLICK ELECTRICAL SPECIFICATIONS
| Description | Min | Typ | Max | Unit |
|---|---|---|---|---|
| Supply Voltage VCC | 3.3 | - | 5 | V |
| External Supply Voltage | 3.3 | - | 5 | V |
| Isolation Voltage | - | - | 5 | kVrms |
| Data Rate | - | - | 100 | Mbps |