DC/DCs for Harsh Environment Applications – The RPxx-RAW

Podcast Transcript

Jeff: Welcome to RECOM's Powerful Podcast, where we discuss new topics and products. I'm Jeff Deutschman, your product moderator. From a quarter watt up to 2kW, whether the power is required for an industrial setting, a new IoT gadget, or a high-end medical-grade device, RECOM has you covered.
In this episode, we'll be talking about the new RECOM railway certified part series, the RPxx-RAW. Louis, what can you tell us about these new parts?

Louis: The RPxx-RAW part series are isolated and regulated DC/DC buck converters. There are three different power levels of this part series, a 3W, 6W, and a 10W. These are named RP03-RAW, RP06-RAW, and RP10-RAW, respectively. Each comes in an industry standard DIP24 package for through-hole mounting onto a PCB.

Jeff: All right, and what kind of input and output voltages are offered with these parts?

Louis: So, this is where these parts are truly special. They all have an ultra-wide 4:1 input range, covering 36V to 160VDC input. There are single output versions ranging from 3.3V to 24V, and dual output voltage options as well.

Jeff: That is an impressive input voltage range. Hey, I could see these parts being used in all sorts of applications, including industrial, not just railway.

Louis: That's right, Jeff. These can accommodate the typical 72V, 96V, and 110V inputs that are common in railway but can be used in many general industry applications with high input voltages as well. One example application could be creating an isolated output rail from a 48V or 36V battery source.

Jeff: Hey, speaking of isolation, what isolation level are these rated for?

Louis: The RPxx-RAW series have reinforced isolation and are rated to withstand 3kVAC for 1min.

Jeff: Excellent. How about the certifications that come with these parts?

Louis: In addition to general industry UL62368-1 safety certifications, these parts have been certified to railway standard EN5155.

Jeff: Outstanding. And what kind of extra features and protections do these parts come with?

Louis: All RPxx-RAW parts have built-in short circuit protection without a recovery. Some other protections include over voltage protection, overload protection, and input under voltage lockout. For additional functionality, these converters have an output voltage trim pin and an on-off control pin.

Jeff: It would be helpful to have a trim function for covering non-standard output voltages. Over what range can I trim the outputs to?

Louis: So, by utilizing an external trim resistor, the output voltage can be trimmed to ±10% of the nominal value. This would also be helpful for providing a bit extra voltage if long PCP traces are being used and it's causing a significant voltage drop at the load.

Jeff: Going back to the railway use, I assume there could be applications with some harsh operating conditions. How does the thermal performance of the RPxx-RAW look?

Louis: So that's a great question. The RPxx-RAW parts are all capable of their full load over an operating range from -40°C up to 90°C, and this is just with natural convection cooling. Ambient temperatures up to 105°C can be realized with some forced air cooling or a load derating.

Jeff: All right. Are there any other considerations to make before I design this into my next high voltage application?

Louis: Yeah, just one. It is recommended to use an input line fuse for protecting the converter. The fuse should be a slow-blow type. The recommended fuse for each part is listed on the datasheet.

Jeff: Excellent. The RP03-RAW, the RP06-RAW, and the RP10-RAW are impressive products. I'm certain all these parts will excel even in some harsh conditions. Louis, thanks a ton.

Louis: No problem, Jeff. Jeff: Well, that about wraps it up for this episode of RECOMs Powerful Podcast. Be sure to listen next time when we delve into the pros of another RECOM topic. As always, please contact your regional sales manager for any samples or pricing information. Our applications engineers are always happy to assist you with any technical questions or requests. You can email them at techsupportamericas@recom-power.com. Until then, have a great day and always remember, RECOM powers your products!