Isolated LED Drivers use a high-frequency transformer to create full galvanic separation between the AC input (primary) and DC output (secondary) sides, eliminating any direct electrical path. Non-isolated drivers rely on simpler inductor-based topologies (buck, boost, or buck-boost), resulting in a direct electrical connection between input and output.
Key technical differences include safety, efficiency, size, and cost. Isolated designs achieve SELV (Safety Extra Low Voltage) compliance, offering superior shock protection, surge immunity, and lower EMI. They are inherently safer but typically 2-5% less efficient (85-92%), larger, heavier, and more expensive due to the transformer. Non-isolated drivers reach 90-95%+ efficiency, are compact, lightweight, and cheaper, but expose the output to mains-referenced voltage, requiring robust Class I grounding and reinforced insulation in the luminaire.
From an application perspective, choose isolated drivers for user-accessible or high-safety environments: residential lighting, retail displays, medical equipment, public fixtures, bathrooms, or outdoor areas with moisture risk-anywhere direct contact is possible or regulations demand SELV. Non-isolated drivers excel in enclosed, inaccessible, or industrial settings: warehouse high-bay lights, sealed vapor-tight fixtures, horticultural grow lights, streetlight modules inside poles, or cost-driven OEM projects where efficiency, size, and budget outweigh isolation needs. Both include full protections (overvoltage, short-circuit, thermal), but isolated types provide extra peace of mind in safety-critical installations.
