guides

Digital Isolator Selection Guide

D

David Chen

Senior FAE - Isolation Products

2026-03-15

Comprehensive guide for selecting the right Novosense digital isolator based on isolation voltage, data rate, channel configuration, and application requirements. Covers key specifications, selection criteria, and design considerations.

Key topics covered include digital isolator, selection guide, isolation voltage, CMTI, design guide. This section provides detailed technical information for engineers designing with novosense products.

For specific application requirements and design assistance, contact novosense's technical support team or refer to the official product documentation and reference designs.

💡 FAE Insights

⚠️ Common Pitfalls

✗ Insufficient CMTI causing false triggering
✗ Wrong default output state for safety requirements
✗ Inadequate working voltage margin
✗ Overlooking propagation delay in timing-critical applications
✗ Poor PCB layout compromising isolation performance

📋 Customer Cases

Motor Drive Manufacturer

Industrial Automation

30kW servo drive with 20kHz PWM

Challenge

Experienced occasional false triggering in high dv/dt environment with previous isolator

Solution

Replaced with NSi8240 featuring 200kV/us CMTI, providing 2.5x margin

Customer Feedback

"Eliminated false triggering, achieved 99.9% uptime over 2 years of operation"

Results

Eliminated false triggering, achieved 99.9% uptime over 2 years of operation

Frequently Asked Questions

1. What is the difference between standard and reinforced isolation?

[Data Pending] Answer to be verified with manufacturer technical support team.

💡 Decision Guide: For 480V equipment or safety-critical applications, select reinforced isolation (5kVrms). For standard 240V industrial equipment, standard isolation provides adequate protection at lower cost.

2. How do I calculate the required CMTI for my application?

[Data Pending] Answer to be verified with manufacturer technical support team.

💡 Decision Guide: Calculate dv/dt from switching parameters, then add 2x safety margin for CMTI selection. Choose Novosense isolators with CMTI rating exceeding your calculated requirement.

3. What PCB layout considerations are important for digital isolators?

[Data Pending] Answer to be verified with manufacturer technical support team.

💡 Decision Guide: Follow datasheet PCB layout guidelines. Verify creepage distances meet requirements for your voltage level. Use proper bypassing and ground plane design. Test isolation integrity with hipot testing.

4. What are the most common design mistakes when implementing Digital Isolator Selection?

[Data Pending] Answer to be verified with manufacturer technical support team.

💡 Decision Guide: Review common pitfalls section carefully. Request design review from BeiLuo FAE before PCB fabrication.

5. How can I get additional technical support for Digital Isolator Selection implementation?

[Data Pending] Answer to be verified with manufacturer technical support team.

💡 Decision Guide: Contact BeiLuo FAE team early in your design cycle. We can provide guidance from concept through production.

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