Alternative T1 (Transformer) for EVL8009-V-00H Reference Design

DC-DC Power Converters
1

Hi.

I am following the EVL8009-V-00H reference design and wanted to know what I can replace the transformer with since I cannot find it online and have not seen a datasheet of it either.

This is what the BOM shows for the part:

1 T1 70μH Transformer,
NS:NP:NS:NA = 9:26:9:8 EP13 Chengdu
Jinzhichuan TBSG13-460

Will appreciate a quick response greatly!

Many thanks,

Tony

2

Coilcraft POE40Q-12 might be worth a shot. Small differences aren’t that important it is in a feedback system. Coilcraft is good with samples

1 Like
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Hi, It looks that the turn ratio of POE40Q-12 (NS:NP:NS:NA = 0.5:1:0.5:0.5) is quite different from that of TBSG13-460. Would that be ok? I found that there is a similar design implemented for MP8008 which use a closed turn ratio => WE7491194912 (NS:NP:NS:NA = 1:3:1:1). Can I use WE7491194912 to replace TBSG13-460 in MP8009 design (12V/2.1A)? The significant difference between EVBs of MP8009 and that of MP8008 is that the former don’t implement with photo-coupler. Would the photo-coupler feedback be a variation factor when I select the flyback transformer? Thanks~ David

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Hi, I am planning to use MP8009 in one of our new designs so I was wondering as well for an alternative transformer.
I have found only two so far with similar turn ratio → 7491195112 (2.67:1:1:1) and POE36PR-12E(1 : 0.375 : 0.375 : 0.375).
Could these replace the transformer of EVL8009-V-00H reference design?? Or if not, could you please suggest an alternative one??

edit: Just to add one more part to the possible alternatives: PA3855.003NL Flyback Transformer from Pulse with ratio 2.67:1:1:1

5

Generic answer: it is not easy to find a pin and function compatible transformer (to be precise: coupled inductur), because there is difference in pin count across the manufacturers (standard counter-clockwise, but also clockwise). In the case of this design, even a standard EP13 core with round core seems to be used (judgement based on the winding optics). For power applications (e.g 30W flyback), an enhanced EP13+ with quadratic core (and quadratic bobbin shape) has become common. E.g. Würth, Coilcraft and Pulse.

I also encountered comparable problems in getting a transformer used in eval kits, e.g. TI’s TPS23731EVM-095, where a transformer by LinkCom is specified.

I think it’s not wise of the evalkit designers to design in transformers from not so established firms where availability generally isn’t a problem, at least from the perspective of engineers in the west. Which could have a negative impact on commercial expectations of new integrated circuits that should be pushed by the help of evaluation kits.