PCB power supplies are smaller and more efficient

Paul Boughton
With the introduction of the ZWS-BAF series of PCB-type AC-DC power supplies, TDK-Lambda UK is effectively improving the total performance of its previous ZWS-AF series. By combining high efficiency even at low load conditions, with a wide operating temperature range, small size and ten-year electrolytic capacitor life, TDK-Lambda says it is reinforcing its competitive advantage in the general industrial equipment market.
Boasting features such as active power factor correction and high input transient protection, the ZWS100BAF and ZWS150BAF series operate from a universal input of 85-265V AC or 120-370V DC to meet a wide range of applications, including factory automation, test and measurement, and LED signage. Offered with a choice of output voltages from 3.3V to 48V, each model in the ZWS-BAF series can be adjusted by up to +/-10 per cent of its nominal voltage to accommodate non-standard system voltages.
In comparison to its first generation ZWS-AF series, TDK-Lambda's intelligent design of the ZWS-BAF PCB layout has minimised internal heat losses, resulting in more compact units. Furthermore, the improved heat dissipation provides a wider operating temperature range of -10 to +70 degrees C, allowing 100 per cent load operation in a 50 degrees C environment; the efficiency of the ZWS150BAF-24 model reaches up to 90 per cent, which is considered high for a PCB-type power supply. Over-current and over-voltage protection circuitry are standard features, and an optional remote on/off is available.
With active power factor correction (PFC) that meets the requirements of EN 61000-3-2, the ZWS-BAF models have a 3kV AC input-to-output isolation and meet conducted and radiated EMC conforming to EN 55011/EN 55022-B, FCC-B, VCCI-B. They are delivered with TDK-Lambda's five-year warranty, are safety-approved to UL/CSA/EN 60950-1 and EN 50178, and are CE marked in accordance with the Low-Voltage Directive.
For more information, visit www.uk.tdk-lambda.com