1. Overview

AC-DC converters are electronic devices that convert alternating current (AC) to direct current (DC). They are critical components in power supply systems for modern electronics, enabling equipment to operate safely and efficiently. External/internal (off-board) converters are designed for integration into systems or as standalone units, serving diverse applications from consumer electronics to industrial machinery. Their importance lies in ensuring stable power delivery, voltage regulation, and compliance with global energy standards.

2. Main Types and Functional Classification

3. Structure and Components

Typical physical structure includes:

• Enclosure: Metal/plastic housing with ventilation slots
• Primary Circuit: Input filter, rectifier bridge, and PFC (Power Factor Correction) circuit
• Transformer: Galvanic isolation with primary/secondary windings
• Secondary Circuit: Output rectifier, LC filter, and voltage regulator
• Control IC: PWM controller for output stability and feedback loop
• Protection Circuits: OVP (Over Voltage), OCP (Over Current), OTP (Over Temperature)

4. Key Technical Specifications

5. Application Fields

• Consumer Electronics: Smartphone chargers, gaming consoles
• Industrial Automation: PLCs, CNC machines, IoT gateways
• Telecommunications: 5G base stations, optical network units
• Medical Equipment: Patient monitors, imaging systems (2xMOPP isolation)
• Data Centers: Server power supplies, storage arrays

6. Leading Manufacturers and Products

7. Selection Recommendations

• Determine required output power with 20% safety margin
• Select appropriate form factor (external/internal) based on system integration needs
• Verify compliance with target market safety standards
• Assess thermal management requirements (convection vs forced-air cooling)
• Consider digital control features for smart power management
• Evaluate MTBF (Mean Time Between Failures) for critical applications

Industry Development Trends

Current trends include:

• Increased efficiency targets (>96%) driven by Energy Star regulations
• GaN/SiC transistor adoption for higher switching frequencies and density
• Smart power systems with IoT connectivity and predictive maintenance
• Wide input voltage ranges (85-305V AC) for global deployment
• Reduced form factors through planar magnetics and 3D packaging
• Environmental compliance (RoHS, REACH) driving lead-free and recyclable designs