RBBA3000 series: 3kW and smaller than a half a chocolate bar

Its dimensions are 63.2mm x 60.6mm x 13.0mm, with a volume of 50cm³. This compact size is made possible by the exceptionally high efficiency of the converter, reaching 96% along a very flat characteristic over load.


This results in an excellent efficiency rating even at low loads. However, at a high power density, the converter needs to be cooled. This is done by dissipating heat through the soldered or screwed baseplate attached to the bottom of the half-brick case. The converter can thus be operated at full power at ambient temperatures and up to 85°C. Above this range, derating becomes an issue. At 25°C and 80% load, the MTBF calculated according to Telcordia SR332 is 1,3 x 106 hours.

The RBBA3000 comes with a built-in current measuring function, doing away with the com-mon problems associated with current measurement in power electronics circuits. The volt-age at the Ishare pin provides the current signal, based on the characteristic shown below in figure 3:

For applications that require more than 50A, two RBBA3000-50 can be operated in parallel. To do this, the two Ishare pins must be connected to ensure equal current distribution to the two converters. In addition, the two converters must have the same settings for input voltage, output voltage, sense pins, etc. For further details, see the RECOM Application Guide.

The actual dimensioning of the input and output filters depends on the application, so we can only consider the worst case here. In order to meet the standards for conducted and radiated noise, we recommend the following filters for the RBBA3000:

We already briefly outlined the potential applications of the RBBA3000. Let us now look in more detail at an application where a variable input voltage (20–60V) needs to be converted into a regulated output voltage of 12V:


To achieve a different output voltage, the only component that needs to be changed is the 36kΩ resistor; see also figure 2.