EFE400M digitally controlled medical power supplies from TDK-Lambda

Leading power supply manufacturer TDK-Lambda EMEA extends its successful range of EFE digitally controlled medical power supplies with the introduction of the 400W, EFE400M Medical range. Combining a 4kVac reinforced input-to-output isolation with dual fusing and an output-to-ground isolation of 1500Vac, the EFE400M meets EN/IEC/UL/CSA 60601-1 safety approvals for medical equipment, making it suitable for use in B (body) and BF (body floating) type medical applications.

Offered with nominal outputs of 12V/33.3A, 24V/16.7A or 48V/8.3A, all models in the EFE400M series deliver 400W continuous power – the 12V & 24V models can deliver 530W peak for 10 seconds – and can easily accommodate non-standard system voltages by precise factory programming. The patented Multi-Resonant Topology helps boost efficiency to typically 90%, and the 8-bit microcontroller provides full digital control of the power supply.

The use of digital control allows the EFE400M to be more efficient, smaller, cooler and more feature rich, consistent with the demand for environmentally-friendly products. Standard features such as redundant operation, (complete with in-built Oring FET) and a high current standby output (5V/2A or 12V/1A) make the supplies equally suitable for high integrity applications including broadcast, instrumentation, routers, servers and security networks. Other suitable applications include ATE and automation equipment.

Offered in a 6.5x3.5” footprint with less than 1U height, the EFE400M achieves typical power densities of up to 17.4W/in3 under peak load conditions and 13.1W/in3 under continuous loading. Case options include open frame, U-Chassis, cover and chassis, and cover, chassis and fan; an additional 12V/1A fan supply is included, if no fan is fitted. All models operate from 90-264Vac input with dual fusing as standard. Earth leakage current is better than 300µA, fully complying with medical safety requirements. Active power factor correction ensures EN61000-3-2 compliance. The digital control and other EMC improving design features, such as the use of SiC diodes, ensure curve B EMC performance with a significant margin.

Further features include remote on/off and power good signals; the isolated standby supply of the EFE400M is not affected by the remote on/off. Since the microcontroller is used to digitally predict the output voltage, the line and load regulation can be changed or fine tuned precisely – this is particularly useful when droop paralleling. Protection circuitry for short circuit, over temperature and over voltage conditions are also included as standard.

All models in TDK-Lambda’s EFE400M range are approved to Edition 2 versions of IEC/EN/UL/CSA 60950-1 for general purpose applications, IEC/EN 61010-1 for laboratory and process control applications and IEC/EN/UL/CSA 60601-1 for medical equipment. In addition, the units carry the CE mark, according to the LV Directive, and come with a three-year warranty.