High Power Joule Thief 1 Watt Cree LED Published February 19, 2012 at 400 × 654 in One Winding Joule Thief ← Previous / High Power Joule Thief 1 Watt Cree LED High Power Joule Thief 1 Watt Cree LED. This board features a high permeability core that allows for a single winding.