400W 3” x 5” medical and industrial power supplies deliver 250W convection/conduction cooled with 400W peak power for extended time periods

Posted by Martin on May 12, 2020
Posted in: Products

TDK Corporation (TSE:6762) announces the introduction of the TDK-Lambda brand CUS400M medical and industrial certified AC-DC power supplies, packaged in the industry standard 3” x 5” footprint. With forced air, the series can provide 400W and 250W can be supplied when convection cooled with a peak capability of up to 400W. The duration period of that peak is up to 30 minutes (40°C ambient, 230Vac input) with a maximum duty cycle of 50%, considerably longer than most products on the market. This makes the CUS400M ideal for applications with a relatively low quiescent power consumption and occasional peak demand, including hospital beds, dental chairs and incubators.

Initially, 12V and 24V outputs are available, with the release of 15V, 19V, 28V, 36V and 48V models later in the year. All models accept an 85 to 264Vac input and have a no-load power consumption of less than 1.3W, when the output is inhibited. A 5V 2A or 12V 1A standby voltage, remote on/off, remote sense, AC fail and an output good signal are optional.

The series has a choice of mechanical configurations. Open frame, baseplate, U-channel and enclosed versions are available now and a top mounted fan version later in the year. To optimise cooling, the underside of the CUS400M circuit board is fitted into a thermally conductive, insulated plastic base (patent pending). This allows heat from the surface mounted power components to be dissipated into a cold plate or the system chassis. The overall size of the open frame model is 77.5mm x 128mm x 39.5mm (W x L x H).

The medical and industrial safety certifications include IEC/EN/ES 60601‑1, IEC/EN/UL 62368‑1 and IEC/EN/UL 60950‑1 with CE marking for the Low Voltage, EMC and RoHS Directives. The units also comply with EN 55011‑B and EN 55032‑B conducted and radiated emissions (Class I and II), and meet the EN 61000‑3‑2 harmonics, IEC 60601‑1‑2 Edition 4 and IEC 61000‑4 immunity standards.

The CUS400M has an input to output isolation of 4,000Vac (2 x MoPP), an input to ground isolation of 1,500Vac (1 x MoPP) and an output to ground isolation of 1,500Vac (1 x MoPP) for suitability in B and BF rated medical equipment. The leakage current is <250µA and touch current is <100µA. The maximum operating, transportation and storage altitude is 5,000m, which supports global use and global sales of end-equipment.

For more information about the full range of TDK-Lambda’s CUS400M series of AC-DC power supplies, please call TDK-Lambda directly on +44 (0)1271 856600 or visit the website at: