Myrra 44266 – PCB-Mountable Transformers

Even though recent failures of vintage HP test equipment have Joe Boeschert a bad name, history has all but vindicated his decision to become a pioneer of switching regulators. Their success has pushed classic transformers into the background – a significant mistake.

In many cases, transformer-based supplies can be more efficient. This is caused by multiple factors: in addition to less EMI issues, a dedicated transformer sometimes is cheaper than the various parts needed to protect the switcher.

One interesting candidate comes from Myrra…

One interesting candidate comes from Myrra – based in France and Poland, the company has a long history of building transformers. One particularly interesting part is the Myrra 44266, and is a member of their family of PCB-mountable transformers.

This is not a hallucination: the transformer comes with hold pins which allow the part to be soldered onto your PCB like any other large inductor. Due to the relatively high weight (which the manufacturer does not specify), using a cable tie or a bit of glue to securely fix the part is recommended.

When installed, the 44266 behaves just like any other transformer – it wants an input voltage of 230 volts AC, and breaks it down to a nominal voltage of 9V. The power rating of 10VA, then, allows us to deduce the maximum current handled by the transformer to be 1.111A.

…the part is certified according to UL 5085, VDE, EN 61558-2-6 and EN 60950

This part differs from its competitors by the wide amount of certifications – the part is certified according to UL 5085, VDE, EN 61558-2-6 and EN 60950. The transformer provides an insulation voltage of up to 4 kV, and promises that the secondary coil is short-circuit proof by design (an interesting document on that is found by Clicking Here. Should disaster ever since your application, the plastic case is self extinguishing according to the UL94-V0 standard.