REGULATED & UNREGULATED DC/DC converter

[ericmar]

Hi,

May I know wats the difference between a REGULATED and an UNREGULATED DC/DC converter? TI has these kind of miniature isolated DC/DC converter. Their DCR01 series is a REGULATED one while their DCV01 series is an UNREGULATED one.

In fact, I would like to find out if these DC/DC converters, which provides only 1000 ~ 1500 Vrms insulation voltage, can be used to implemented in a Class II BF medical device or not? Is the insulation voltage high enough? Would they fail to meet the requirement?

Is there any other smaller miniature isolated DC/DC converter available in the market now? I know ADI had a new part coming end of this year, their ADuM524x, but the integrated DC/DC converter also can provide only up to 1000Vrms insulation voltage. This is definitely a good chip if they can increase the insulation voltage to say 4kV as this is a digital isolator with integrated DC/DC converter which is small and good for industry and medical application.

Thanks for any help in advance.

Regards,
Eric

 

[IanP]

The difference between unregulated and regulated dc-dc converter is the same as between unregulated and regulated power supply: in regulated the output voltage is stabilized and kept at constant (well, almost) level, in uregulated voltage drops with load (no load voltage can be >20% higher than full load) ..
Most of these miniature dc-dc converters have uregulated output ..
You can find assorted products with 3kV or even 6kV voltage isolation, for example, NMV-series is rated for 3kV and NMS-series is rated for 6kV (C & D Technology, both unregulated), REC5 or REC3-series (from RECOM, regulated output)) are rated for 4kV isolation ..

Regards,
IanP

 

[ericmar]

hi IanP,

Thanks for help!

Unfortunately, the DC/DC converters from RECOM are even bigger than TI's one.

 

[IanP]

What physical size are you after, and can you use converters with unregulated output? Unregulated doesn't mean useless or bad, and in many applicatins they are almost as good as regulated ..
Here are some examples from MORNSUN ( https://www.mornsun-power.com/ ), especially 3kV ET subminiature series ( **broken link removed** and click on Fixed input - unregulated output ) ..

Regards,
IanP

 

[ericmar]

Size is a very big problem for me! In fact, I m looking for something smaller than the TI's DCR01/DCV01 series (SMD type) which is about 18mm(L)x11mm(W)x2.65mm(H).

Also, the higher the insulation the better!

 

[nikhilele]

can I have DC/DC regulator having buck/boost both features which can give 5V@500mA o/p from 4.8V to 7.5V range. but it should be below 1$.

And a 5V to 12V@1A Step-up
I have seen LM78S40 for this which is less than 1$.

Am I distrubing your discussion by asking this here if yes tell me I will post it in new thread.

 

[IanP]

I don't think you will be able to find any smaller DC-DC converters than the DCR01/DCV01 ..

Regards,
IanP

Dear nikhilele,
New thread wouldn't hurt ..

 

[ericmar]

I don't think you will be able to find any smaller DC-DC converters than the DCR01/DCV01 ..

Regards,
IanP

Dear nikhilele,
New thread wouldn't hurt ..

Dear IanP,

Like wat i said earlier, the ADI is desiging a digital isolator with integrated DC/C converter (conforms EN60601) but it wont be released till early next year according to them and the ADuM524x series will only be released end of this year. According to the Pre-released datasheet of this ADuM524x, the dimension will be comparably small to TI's DCR01/DCV01 series.

Regards,
Eric

 

[freepoint]

where do yo cite this picture?