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Transformers

Low-Profile Transformers

Also listed as Flat Type Transformers

2–30 VA, UI cores, dual 115 V primary, EN 61558

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Low-profile transformers use UI laminations wound on a dual-bobbin former to hold overall height down for shallow enclosures and stacked board assemblies. The current range spans 2 to 30 VA across the UI30 and UI39 sub-series, with the withdrawn UI21 and UI48 series still documented for designs already using them. Unlike the PCB-mount line, every part carries two 115 V primary windings, so the same transformer runs on 115 V mains with them in parallel or 230 V with them in series — which is what makes this the easier family to design into a North American product. The dual-bobbin construction keeps primary and secondary windings physically separated across the core, simplifying mains-isolation creepage distances in a reduced-height package.

Insulation

Insulation and impregnation are specified as air, oven-dried varnish, polyurethane coating, or epoxy potting, selected to the unit's environmental exposure and required creepage and clearance.

Certifications

  • EN 61558

Sub-series

  • UI30
  • UI39
An Aslan 18 VA UI39 low-profile transformer
Part numbers
98

70 in the current catalog, 28 discontinued

Power range
2–30 VA

0.8–65 VA including discontinued series

Secondary voltages
6–24 V

6, 7.5, 9, 12, 15, 18, 24 V per winding, single or dual

Datasheets
14

One per series, free to download

Primary voltage: 2 × 115 V on every part in this family

Two 115 V primary windings, so the same part runs on 115 V mains with the windings in parallel or 230 V with them in series. Send us the input voltage you are designing to and we will confirm the winding.

Find a part number

Every part number in the family. Narrow by core, secondary voltage, winding count, cover style, or availability — then open the part for its full figures and datasheet.

98 rows

Low-Profile Transformers — published specifications
ASL6002060.82 × 6 V66.7UI21Standard—Discontinued
ASL6002080.82 × 7.5 V53.4UI21Standard—Discontinued
ASL6002090.82 × 9 V44.4UI21Standard—Discontinued
ASL6002120.82 × 12 V33.3UI21Standard—Discontinued
ASL6002150.82 × 15 V26.7UI21Standard—Discontinued
ASL6002180.82 × 18 V22.2UI21Standard—Discontinued
ASL6002240.82 × 24 V16.6UI21Standard—Discontinued
ASL60040612 × 6 V83.3UI21Standard—Discontinued
ASL60040812 × 7.5 V33.3UI21Standard—Discontinued
ASL60040912 × 9 V55.6UI21Standard—Discontinued
ASL60041212 × 12 V41.7UI21Standard—Discontinued
ASL60041512 × 15 V33.3UI21Standard—Discontinued
ASL60041812 × 18 V27.7UI21Standard—Discontinued
ASL60042412 × 24 V20.8UI21Standard—Discontinued
ASL62020622 × 6 V167UI30Standard—Active
ASL62020822 × 7.5 V133UI30Standard—Active
ASL62020922 × 9 V111UI30Standard—Active
ASL62021222 × 12 V83.3UI30Standard—Active
ASL62021522 × 15 V66.6UI30Standard—Active
ASL62021822 × 18 V55.5UI30Standard—Active
ASL62022422 × 24 V41.6UI30Standard—Active
ASL62120642 × 6 V333UI30Standard—Active
ASL62120842 × 7.5 V266UI30Standard—Active
ASL62120942 × 9 V222UI30Standard—Active
ASL62121242 × 12 V166UI30Standard—Active
ASL62121542 × 15 V133UI30Standard—Active
ASL62121842 × 18 V111UI30Standard—Active
ASL62122442 × 24 V83UI30Standard—Active
ASL62220662 × 6 V500UI30Standard—Active
ASL62220862 × 7.5 V400UI30Standard—Active
ASL62220962 × 9 V333UI30Standard—Active
ASL62221262 × 12 V250UI30Standard—Active
ASL62221562 × 15 V200UI30Standard—Active
ASL62221862 × 18 V166UI30Standard—Active
ASL62222462 × 24 V125UI30Standard—Active
ASL623206102 × 6 V833UI30Standard—Active
ASL623208102 × 7.5 V666UI30Standard—Active
ASL623209102 × 9 V555UI30Standard—Active
ASL623212102 × 12 V416UI30Standard—Active
ASL623215102 × 15 V333UI30Standard—Active
ASL623218102 × 18 V277UI30Standard—Active
ASL623224102 × 24 V208UI30Standard—Active
ASL624206162 × 6 V1,333UI30Standard—Active
ASL624208162 × 7.5 V1,066UI30Standard—Active
ASL624209162 × 9 V888UI30Standard—Active
ASL624212162 × 12 V666UI30Standard—Active
ASL624215162 × 15 V533UI30Standard—Active
ASL624218162 × 18 V444UI30Standard—Active
ASL624224162 × 24 V333UI30Standard—Active
ASL650206102 × 6 V833UI39Standard—Active
ASL650208102 × 7.5 V666UI39Standard—Active
ASL650209102 × 9 V555UI39Standard—Active
ASL650212102 × 12 V416UI39Standard—Active
ASL650215102 × 15 V333UI39Standard—Active
ASL650218102 × 18 V277UI39Standard—Active
ASL650224102 × 24 V208UI39Standard—Active
ASL651206142 × 6 V1,166UI39Standard—Active
ASL651208142 × 7.5 V933UI39Standard—Active
ASL651209142 × 9 V777UI39Standard—Active
ASL651212142 × 12 V583UI39Standard—Active
ASL651215142 × 15 V466UI39Standard—Active
ASL651218142 × 18 V388UI39Standard—Active
ASL651224142 × 24 V291UI39Standard—Active
ASL652206182 × 6 V1,500UI39Standard—Active
ASL652208182 × 7.5 V1,200UI39Standard—Active
ASL652209182 × 9 V1,000UI39Standard—Active
ASL652212182 × 12 V750UI39Standard—Active
ASL652215182 × 15 V600UI39Standard—Active
ASL652218182 × 18 V500UI39Standard—Active
ASL652224182 × 24 V375UI39Standard—Active
ASL653206242 × 6 V2,000UI39Standard—Active
ASL653208242 × 7.5 V1,600UI39Standard—Active
ASL653209242 × 9 V1,333UI39Standard—Active
ASL653212242 × 12 V1,000UI39Standard—Active
ASL653215242 × 15 V800UI39Standard—Active
ASL653218242 × 18 V666UI39Standard—Active
ASL653224242 × 24 V500UI39Standard—Active
ASL654206302 × 6 V2,500UI39Standard—Active
ASL654208302 × 7.5 V2,000UI39Standard—Active
ASL654209302 × 9 V1,666UI39Standard—Active
ASL654212302 × 12 V1,250UI39Standard—Active
ASL654215302 × 15 V1,000UI39Standard—Active
ASL654218302 × 18 V833UI39Standard—Active
ASL654224302 × 24 V625UI39Standard—Active
ASL671406502 × 6 V3,750UI48Standard—Discontinued
ASL671408502 × 7.5 V3,000UI48Standard—Discontinued
ASL671409502 × 9 V2,500UI48Standard—Discontinued
ASL671412502 × 12 V1,875UI48Standard—Discontinued
ASL671415502 × 15 V1,500UI48Standard—Discontinued
ASL671418502 × 18 V1,250UI48Standard—Discontinued
ASL671424502 × 24 V1,041UI48Standard—Discontinued
ASL672406652 × 6 V5,417UI48Standard—Discontinued
ASL672408652 × 7.5 V4,333UI48Standard—Discontinued
ASL672409652 × 9 V3,611UI48Standard—Discontinued
ASL672412652 × 12 V2,708UI48Standard—Discontinued
ASL672415652 × 15 V2,167UI48Standard—Discontinued
ASL672418652 × 18 V1,806UI48Standard—Discontinued
ASL672424652 × 24 V1,350UI48Standard—Discontinued

Figures are reproduced from the factory datasheets linked below. Current is quoted per secondary winding, so a dual-winding part delivers the listed current on each of its two windings. Rows marked discontinued are kept for designs already using them and cannot be ordered.

UI21, UI48 have been withdrawn from the current catalog

28 of the part numbers above are discontinued and cannot be ordered. Their pages and datasheets stay published for anyone maintaining an existing design, and each one lists the active parts it can be requoted against where the range still reaches that rating.

The current range tops out at 30 VA. Above that we build to order — send the specification and we will quote the wind.

Datasheets

14 factory datasheets cover this family, one per series. Each gives the dimensions, winding table, and pin layout for the part numbers built on it — all of them hosted here, indexed below and linked from every part page.

Browse the datasheet index

Series and datasheets

Aslan publishes one datasheet per series — a core size, a rating, and a cover style, covering the part numbers wound on it. All 14 are hosted here.

UI21

0.8–1 VA · 2 datasheets

Core withdrawn

UI48

50–65 VA · 2 datasheets

Core withdrawn

Typical applications

  • Slim wall-mount and desktop power adapters
  • Height-constrained control panel and enclosure designs
  • LED driver and lighting control circuits
  • Instrumentation and metering low-voltage supplies
  • Small appliance and HVAC control boards
  • Battery-charger primaries in low-profile enclosures

Next step

Not finding the exact part?

Three ways in, and each one arrives with Low-Profile Transformers already attached.

Cross-reference

Replacing a Würth, Coilcraft, Pulse, TDK, or Bourns part? Send us the part number.

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Custom build

Need a different power rating, size, or termination?

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Samples

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