Can I get Transformerless ac-dc for 30-40W - Page 1
Forum section: electronics / beginners

author: muthukural001
author_rank: Regular Contributor
timestamp: September 09, 2020, 09:44:45 am
content: Hello All,I am looking for transformerless ac-dc converter module which supports 30W-40W...I have looked at monolithic's AC-DC module solution and looks like they do not have transformerless for 30W-40W...If anyone have come across this, please share...Thanks and Regards,Muthu

author: capt bullshot
author_rank: Super Contributor
timestamp: September 09, 2020, 10:13:29 am
content: What about these:https://www.mouser.de/Search/Refine?N=18337911SCNR, You'd have to give more specific specifications for better answersAnyway, a "common" AC/DC for e.g. 230V AC to 12V DC at 40W wouldn't be transformerless at all, since it's technically no good to not use a transformer in this particular case.

author: muthukural001
author_rank: Regular Contributor
timestamp: September 09, 2020, 01:37:47 pm
content: Hi,Our req is 5V 6A (30W) output from a AC-DC converter module which should be transformerless...If 30W without transformer is not technically possible, we are even okay with 15W transformerless ac-dc...Please anyone suggestThanks and Regards,Muthu

author: capt bullshot
author_rank: Super Contributor
timestamp: September 09, 2020, 01:58:52 pm
content: Quote from: muthukural001 on September 09, 2020, 01:37:47 pmIf your input is e.g. 8V AC, for sure you can build a transformerless suppy module outputting 5V DC / 6A using a linear regulator.What's the reason for "transformerless" ?Under "normal" circumstances, there's no reasonable way to build such a supply (no matter if 15W or 30W) operating with mains voltage input. A typical "transformerless" DC supply running from mains can be either built using a high voltage buck converter, or a capacitive dropper circuit. The latter one typically delivers some 10mA, the usual single inductor buck converters operating from mains are in the 1W output power ballpark.

author: bdunham7
author_rank: Super Contributor
timestamp: September 09, 2020, 02:05:59 pm
content: Quote from: muthukural001 on September 09, 2020, 01:37:47 pmIs the AC the 230VAC mains? Or is it something else?And by 'transformerless', do you mean you don't want a typical step-down transformer followed by a bridge and linear regulator? Or that the device, for some odd reason, cannot contain any inductors at all? That would be a pretty odd requirement and makes a simple task almost impossible.

author: muthukural001
author_rank: Regular Contributor
timestamp: September 09, 2020, 02:40:44 pm
content: Hi guys,What about our mobile charger ?. It should have transformer but not a bulky one, that's why they are light weight and compact. I think that I should use kind of that transformer to acheive 15W (5V 3A)... For 30W support, I am not sure the same light weight transformer will do the job or it will require a bulky one.

author: tunk
author_rank: Super Contributor
timestamp: September 09, 2020, 03:16:09 pm
content: That phone charger is a switched-mode power supply (SMPS)as is almost all of todays power supplies:https://en.wikipedia.org/wiki/Switched-mode_power_supplyEdit: and it should not be a problem to find one with 5V and 30W.

author: bdunham7
author_rank: Super Contributor
timestamp: September 09, 2020, 03:25:39 pm
content: Quote from: muthukural001 on September 09, 2020, 02:40:44 pmOK, so what you apparently need is readily available commercially, although it is not technically "transformerless":https://www.meanwell.com/Upload/PDF/IRM-30/IRM-30-SPEC.PDF

author: langwadt
author_rank: Super Contributor
timestamp: September 09, 2020, 03:57:26 pm
content: why transformerless?

author: dmendesf
author_rank: Frequent Contributor
timestamp: September 12, 2020, 03:07:32 am
content: https://www.st.com/content/st_com/en/products/power-management/ac-dc-converters/high-voltage-converters/viper/viper53e-e.html

author: TheHolyHorse
author_rank: Regular Contributor
timestamp: September 15, 2020, 06:26:20 am
content: I think his requirement is compact size rather than transformer less.