Small 1W and 2W isolated dc

Würth Elektronik has added devices with continuous short-circuit protection to its MagI3C-FISM family of 1W or 2W isolated un-regulated dc-dc converters.

Würth Elektronik has added devices with continuous short-circuit protection to its MagI3C-FISM family of 1W or 2W isolated un-regulated dc-dc converters.

"The entire product line is certified to the current UL standard UL62368-1, but the new modules offer even more safety. They cannot be destroyed by short circuits and can withstand their isolation voltage of 1.5 kV for the SIP-4 modules and 3 kV for SIP-7 and SMT-8 for a full 60 seconds," according to the company.

Efficiency is around 80% depending on load and other caveats, and operation is across -40 to 105°C, with de-rating beginning somewhere in the range 70 to 85°C depending on the part.

In all cases, nominal output voltage for the new devices is 5V, while the different parts have nominal inputs of 5V (4.5 – 5.5V), 12V (10.8 – 13.2V) or 24V (21.6 – 26.4V).

SIP-7 (7 x 19.6 x 10.6mm high) and STP8 (13.4 x 11.4 x 7mm) converters are nominally 2W, and the SIP-4s (6 x 11.6 x 10.6mm) are 1W.

Input and output capacitors are included within the modules, but additional LC input filtering may be needed depending on EMC requirements.

"Radiated and conducted emissions of the modules are below the limits of the EN55032 / CISPR32 Class B," said Wurth.

Functional isolation can be used to prevent ground loops and ground level offsets, as well as to reduce interference in signal path or sensor systems.

Isolation can also be important when designing power supplies for interfaces and microcontrollers within test equipment or industrial electronics.

Finally, the outputs of isolated power supplies can be connected in series to create higher voltages or +/- voltage pairs.

To find the new parts, click on this link, scroll down to the table, and be guided by the inclusion or lack of short-circuit protection (or the ‘new’ logos in the left hand column if they are still there).