Power supplies for applications with low quiescent power consumption

TDK Corporation has introduced 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 provided when convection cooled with a peak capability of up to 400W. The duration of that peak is up to 30 minutes (40C ambient, 230VAC input) with a maximum duty cycle of 50%, notably longer than many products on the market. This makes the device excellent for applications with a relatively low quiescent power consumption and occasional peak demand, such as hospital beds, dental chairs and incubators.

Initially, 12V and 24V outputs are offered, with 15V, 19V, 28V, 36V and 48V models appearing later in the year. All models accept an 85VAC to 264VAC input and have a no-load power consumption lower 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 variety of mechanical configurations. Open frame, U-channel, baseplate and enclosed versions are provided now and a top-mounted fan version later in the year. To optimise cooling, the underside of the device's circuit board is fitted into a thermally conductive, insulated plastic base (patent pending).

The medical and industrial safety certifications comprise 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.