A high speed logic signal level shifter is comprised of: a logic signal buffer for receiving logic signal information and having true and complement state differential outputs; a binary flip-flop circuit with set and reset inputs; a first coupling capacitor connected from the true buffer output to the set input of the binary flip-flop circuit; and a second coupling capacitor connected from the complement buffer output to the reset input of the binary flip-flop circuit. The high speed logic signal level shifter transfers a fast logic signal across a high voltage difference by making use of rapid voltage changes transmitted through small capacitors. The signal changes carried by the capacitors are about 10 times faster than any expected voltage transient on VPP or VNN. Furthermore, the differential coupling circuit is used to provide enhanced protection against undesired circuit switching during supply voltage changes.