250W convection cooled power supply eliminates audible noise

July 25, 2013 // By Graham Prophet
TDK-Lambda's CUS250LD series of low profile, AC-DC power supplies features low profile, high efficiency and wide AC input range.

These single-output supplies provide 250W of output power with convection cooling; requiring no fans, this design eliminates the need for fan maintenance, and reduces acoustic noise and vibrations. In addition, they feature a low profile of only 30 mm and a compact footprint of 198 x 101.6 mm, suiting them to light industrial, LED signage, communications, broadcast, point-of-sale, IT, and test and measurement equipment.

The supplies operate from a universal input of 85-264 Vac, 47-63 Hz, with PFC, enabling them to be used anywhere in the world. They can also operate from a 120-370 Vdc input. These units have an input-to-output withstand voltage of 3 kVac. The CUS250LD series is available with nominal output voltages of 3.3V, 4.2V, 5V, 12V, or 24 Vdc, all of which have a ±10% user adjustment range.

The convection cooled operating temperature range is from -25°C to +70°C with derating above +40°C and efficiency is up to 90%. Other standard features include overvoltage and overcurrent protection. The CUS250LD series features global ITE and general purpose safety agency certifications according to UL/CSA/EN60950-1. CE marked in accordance with the LV Directive and RoHS Directive, the power supplies conform to EN55022-B and FCC Class B for conducted and radiated EMI and include a three-year warranty.

TDK-Lambda; www.uk.tdk-lambda.com/cus