Lately I have been asked if there is a power and charging tip for the ACP71 or ACP77 to use with the Microsoft Surface Pro 3. The short answer is, “No.”
The issue for power and charging the Surface Pro 3, or other Surface for that matter, is not one of mechanical compatibility, a charging tip circuit, or the power (Watts). These new tablets are powered by a 5VDC and 12VDC PSU (aka “brick”). Both of these voltages are supplied through the Microsoft magnetic power tip. The Targus ACP71 and ACP77 both output a single 19VDC. This voltage is very popular for input to the current generation of PC, ultra-books, 2-in-1s, etc., but more an more tablets are going to a lower supply voltage. To be used with the Surface(s), the ACP71/77 voltage with have to be converted to the compatible Surface supplies, but to date Targus does not have a solution.