650W modular power supplies offer up to 10 outputs with BF ready isolation and low acoustic noise

Posted by Hannah on June 21, 2019
Posted in: News, Products

TDK Corporation is pleased to announce the introduction of the TDK-Lambda brand QM4 series of AC-DC modular power supplies reducing the series’ footprint by 15%. The 108mm wide QM4 can accept up to four single or dual output modules and a dual output standby/signal board to provide up to 10 outputs. All models in the QM series feature low acoustic noise and full MOPPs isolation. With medical and industrial safety certifications, the QM series is suitable for use in a wide range of applications, including BF rated medical equipment, test and measurement, broadcast, communications and renewable energy.

The QM4 can deliver 650W output power with a 180-264Vac input and 550W with a wide range 90-264Vac input. Output voltages from 2.8V to 105.6V can be specified and an optional standby/signal module can be fitted. This provides a choice of one or two standby voltages (5V, 12V and 13.5V at up to 2A), a PMBus™ communication interface, unit inhibit or enable, and an AC Good signal.

The units can operate in ambient temperatures of -20 to +70ºC, derating output power and output current by 2.5% per ºC above 50ºC. Overall case dimensions are a compact 108 x 63.5 x 270mm (W x H x D), and the weight is between 1.125kg and 1.845kg, depending on the module configuration. The QM series’ operating efficiency is up to 91%, reducing internal heat losses and allowing the use of a low speed, low audible noise fan for cooling. This enhances the patient/user experience and increases reliability. The series is also covered by a seven-year warranty.

The QM series power supplies are certified to IEC/EN/UL/CSA 60601‑1, ANSI/AAMI ES 60601‑1, IEC/EN 61010‑1 and IEC/EN/UL/CSA 60950‑1, with CE marking for the Low Voltage, EMC and RoHS2 Directives. With an input to output isolation of 4,000Vac (2 x MOPPs), 1,500Vac input to ground (1 x MOPP) and 1,500Vac (1 x MOPP) output to ground, the series can be used in BF rated medical equipment such as blood pressure monitors and incubators. The QM4 has a maximum earth leakage current of 300µA, while still complying with the EN61000-6-3:2007 and EN60601-1-2:2015 (curve B conducted and radiated) emission standards. The units also meet the EN60601-1-2 and EN61000-6-2 immunity standards.

Selecting products from the QM series has been made extremely simple using an online configurator, which provides an optimised module selection with a choice of signals, leakage current and standby voltages. Upon entering the desired output voltages and currents, the configurator will automatically produce a short 7 digit code to facilitate easy order placement.

For more information about the QM series of AC-DC modular power supplies from TDK-Lambda, please call TDK-Lambda directly on +44 (0)1271 856600 or visit the TDK-Lambda website at:

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