2.4.2.3 Digital Isolators for DC Analog Output Control Signals

The DAC and XTR300 device are isolated from the MCU using digital isolators. The ISO7341FC digital isolator supports data rates up to 25 Mbps with greater than 4 kV of galvanic isolation. To communicate with the DAC, control the XTR300 outputs, and monitor the XTR300 outputs, a total of six outputs and two digital inputs are required. To provide these essential outputs and inputs, two ISO7341FC devices are used and each feature three output channels and one input channel.

The following circuit diagram in Figure 13 shows all eight signals interfacing:

Figure 13. Circuit Diagram of Digital Isolators Interface

The ISO7341FC device provides 4242-V_PK basic isolation.

To obtain reinforced isolation, use the ISO7841 device, which provides an 8000-V_PK reinforced isolation.