Open up a new image, then type in some text like I have done.
After that, duplicate that text layer by dragging it into the "new layer" button in the layers palette.
Next, rasterize that layer by going to Layer > Rasterize > Type.
Now go to Filter > Pixelate > Mosaic. Enter the cell size setting to 8.
Next, do it again and go to Filter > Pixelate > Mosaic and enter the cell size 5 or 7.
Go to Filter > Stylize > Find Edges.
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