Digital Isolators

Part Number	Description / PDF	Quantity
SI88341EC-IS Silicon Labs	DGTL ISO 5000VRMS 4CH GP 24SOIC	0
SI8621BC-B-ISR Silicon Labs	DGTL ISO 3750VRMS 2CH GP 8SOIC	0
SI8652BD-B-IS Silicon Labs	DGTL ISO 5000VRMS 5CH GP 16SOIC	1472
SI8610AB-B-IS Silicon Labs	DGTL ISO 2500VRMS 1CH GP 8SOIC	133
SI8631EC-B-IS1R Silicon Labs	DGTL ISO 3750VRMS 3CH GP 16SOIC	0
SI8463BA-B-IS1 Silicon Labs	DGTL ISO 1000VRMS 6CH GP 16SOIC	0
SI8452AB-B-IS1 Silicon Labs	DGTL ISO 2500VRMS 5CH GP 16SOIC	0
SI8663BD-B-IS Silicon Labs	DGTL ISO 5000VRMS 6CH GP 16SOIC	0
SI8640BC-B-IS1R Silicon Labs	DGTL ISO 3750VRMS 4CH GP 16SOIC	0
SI8441BB-D-IS Silicon Labs	DGTL ISO 2500VRMS 4CH GP 16SOIC	0
SI8431AB-D-IS1R Silicon Labs	DGTL ISO 2500VRMS 3CH GP 16SOIC	0
SI8460BA-B-IS1 Silicon Labs	DGTL ISO 1000VRMS 6CH GP 16SOIC	0
SI8050AA-B-IUR Silicon Labs	DGTL ISO 1000VRMS 5CH GP 16QSOP	0
SI88242EC-IS Silicon Labs	DGTL ISO 5000VRMS 4CH GP 20SOIC	0
SI8452BA-B-IS1 Silicon Labs	DGTL ISO 1000VRMS 5CH GP 16SOIC	0
SI8652EC-B-IS1R Silicon Labs	DGTL ISO 3750VRMS 5CH GP 16SOIC	0
SI8462BA-A-IS1 Silicon Labs	DGTL ISO 1000VRMS 6CH GP 16SOIC	0
SI8455BB-B-IS1 Silicon Labs	DGTL ISO 2500VRMS 5CH GP 16SOIC	0
SI8405AB-A-IS1R Silicon Labs	DGT ISOL 2500VRMS 4CH I2C 16SOIC	0
SI8441BB-D-IS1R Silicon Labs	DGTL ISO 2500VRMS 4CH GP 16SOIC	0

Digital Isolators

1. Overview

Digital isolators are electronic components that enable signal transmission between circuits or systems with different voltage levels while maintaining electrical isolation. They utilize semiconductor technologies (e.g., capacitive, inductive, or optical coupling) to replace traditional optocouplers. These devices are critical in modern systems for ensuring safety, reducing noise interference, and enabling communication in high-voltage environments.

2. Main Types and Functional Classification

Type	Functional Features	Application Examples
Capacitive Isolators	Use high-frequency capacitive coupling for signal transfer. Low power consumption, supports high data rates.	Industrial motor drives, PLC systems
Inductive (Magnetic) Isolators	Utilize miniature transformers for isolation. High noise immunity, supports bidirectional communication.	Automotive BMS, battery chargers
Optocoupler-Based Digital Isolators	Hybrid design combining LED and CMOS detectors. Low cost, moderate speed.	Consumer electronics, home appliances
Multi-Channel Isolators	Integrate multiple isolation channels in one package. Supports complex signal routing.	Data acquisition systems, industrial IoT gateways

3. Structure and Components

A typical digital isolator consists of: (1) Input circuit with signal conditioning; (2) Isolation barrier (e.g., SiO2 capacitive layer or micro-transformer core); (3) Output circuit with amplification/reconstruction; (4) Dual-die packaging with reinforced insulation. Advanced products integrate signal and power isolation in single chips.

4. Key Technical Specifications

Parameter	Unit	Importance
Isolation Voltage (Viso)	Vrms	Determines safety level (e.g., 2500-5000Vrms for industrial use)
Data Rate	Mbps	Defines maximum signal transmission speed (1-150 Mbps)
Propagation Delay	ns	Impacts system timing accuracy (Typ. 10-50 ns)
Power Consumption	mW	Crucial for battery-powered devices
Operating Temperature	C	Specifies environmental tolerance (-40 to +125 C)

5. Application Fields

Industrial automation (PLC, motor drives)
Medical equipment (ECG machines, patient monitors)
Automotive systems (BMS, OBC for EVs)
Renewable energy (solar inverters, grid-tied systems)
Telecommunications (5G base stations, optical transceivers)

6. Leading Manufacturers and Products

Manufacturer	Representative Product	Key Specifications
Analog Devices	ADN4654	150Mbps, 5kVrms isolation, 4-channel
Texas Instruments	ISO7841	100Mbps, 8kV CMTI, quad-channel
Silicon Labs	SI8640	150Mbps, 2.5kVrms, 4-channel
Infineon	BDx183	100Mbps, reinforced isolation, automotive-grade

7. Selection Guidelines

Define isolation voltage and safety certification (e.g., UL, VDE)
Match data rate with system requirements
Consider channel count and directionality
Evaluate power budget and PCB space constraints
Check environmental specifications (temperature, vibration)

8. Industry Trends

Future development focuses on: (1) Integration of isolation and level-shifting functions; (2) 3D packaging for miniaturization; (3) Enhanced immunity to electromagnetic interference (EMI < 150 V/m); (4) System-level isolation solutions combining signal/power transfer. The market is projected to grow at 12% CAGR until 2028, driven by EV and industrial IoT adoption.

Application Case

In electric vehicles, digital isolators like TI's ISO7741 are used in battery management systems to isolate high-voltage battery packs (up to 1000V) from low-voltage control circuits, enabling safe CAN bus communication with 50kV/ s common-mode transient immunity (CMTI).