How do I zoom to a specific scale programmatically?

Hi,

I modified the CoordinateWidget so that the current scale value of the map is displayed in the lower left corner of the map.

Attachment 29949

However I don't just need to see it, I want the user to be able to specify the scale too.
Which is why I made the scale displayed in a TextInput.

I thought there would be a simple function in the API to let me zoom the map by passing a specific scale, but I didn't find one.
It has to be possible since the API Navigator component (com.esri.ags.components.Navigation) does it with the LODs specified in the config.xml.

Anyone already did something like this?

Thanks

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