Abstract: A dual data rate flip-flop circuit for reducing single event upset errors in the flip-flop circuit including two or more latch circuits connected in parallel. The latch circuits each have a clock input, data input, and latch circuit output. The dual data rate flip-flop circuit also includes a C-element, which has a plurality of inputs and a C-element output. The outputs of the latch circuits are provided to inputs of the C-element, and a keeper circuit is connected to the C-element output. An output buffer inverter connects to the C-element output and has an output corresponding to the dual data rate flip-flop circuit output.