Ultra-wide voltage input power module

Paul Boughton

Ericsson has introduced a new 50W DC-DC converter module that targets Power-over-Ethernet (PoE) applications. 

The PKU5510E converter features an ultra-wide input range of 18V to 75V, which means that the device is also suitable for 24V or 48V telecom systems and combines the thermal enhancements integrated in the recently announced PKU4116C module together with an optimized fly-forward topology. This means the module can deliver an output current of 15A at 3.3V output with functional isolation of 2250VDC that meets the requirements specified by the IEEE802.3 Ethernet networking standard, and also meets Basic Insulation requirements according to IEC/EN/UL60950.

The module has been designed for applications that have to accommodate both telecom system bus voltages of 24V and 48V, while also being a best-in-class product to supply voltages to Power-over-Ethernet based applications such as remote antennas, WIFI repeaters, basestation microcells, CCTV/camera monitoring systems and a variety of different sensors.

With its ultra-wide input and high efficiency, the PKU5510E is also aimed at industrial applications and many others that use remote power feeds, where a module is required to operate irrespective where it is connected or indeed of the length of the line cable. 

In addition, the wide input range of PKU5510E offers another benefit for applications that require a hold-up capacitor to prevent the loss of vital data in the case of line disruption. As the module can operate at 18V, a hold-up capacitor can maintain voltage for a longer period of time when compared to a competitive power module with a narrower input range. And because of the module’s wide range of operation, this can even reduce the amount of capacitors required and therefore reduce cost.

Designed for applications that are subject to peak currents and environment with very low natural convection or airflow, the PKU5510E embeds a unique overload protection system. In these types of applications, the overload protection must prevent false triggering while simultaneously guaranteeing reliable protection from overloading. A solution for this complex situation has been achieved by combining two Over-Current Protection (OCP) methods.

In the case of a short-duration overload, the hiccup-mode OCP uses a tightly controlled cycle-by-cycle current limitation; and in the case of longer overload, the hiccup-mode OCP will trigger for conventional hiccup protection.

However, protection is not just limited to two hiccup modes, as the hiccup activation time is proportional to temperature and becomes shorter with an increase in temperature, thereby limiting the energy dissipated during this period. Following activation of the Over-Temperature Protection (OTP), the module thoroughly checks the OTP threshold to prevent any restart that could damage the module.

Available in an industry-standard sixteenth-brick footprint – with dimensions of 33 x 22.9mm and a low-profile height of only 9.4mm (1.3 x 0.9 x 0.37in), the device delivers up to 50W, and provides up to 92 per cent efficiency at 50 per cent load and 27V input, guaranteeing low power dissipation and reduced energy consumption.

Built upon an enhanced thermal layout, the PKU5510E can be used in applications that have limited airflow, which is usually the case in low-power PoE systems. In the case of natural convection, the module delivers full performance up to 80°C; and when the system experiences 3.0m/s convection cooling, full power can be delivered up to 96°C. Offering an MTBF (Mean-Time-Before-Failure) of 4.9 million hours, the PKU5510E meets safety requirements according to IEC/EN/UL 60950-1 and offers input/output isolation of 2250Vdc. PKU5510E also includes various protection features, including Output-over-Voltage Protection (OVP), input-under-voltage shutdown, Over-Temperature Protection (OTP), output short-circuit protection and pre-biased output.

For more information, visit www.ericsson.com/powermodules