The invention provides a circuit comprising a first element; a second element; a first transistor; a second transistor; and a capacitor, wherein an output of the first element is electrically connected to an input of the second element, and an output of the second element is electrically connected to an input of the first element, wherein the input of the first element is electrically connected to a first wiring configured to be supplied with an input signal and the output of the first element is electrically connected to a second wiring configured to be supplied with an output signal, wherein a channel formation region of the first transistor includes an oxide semiconductor, wherein one of a source and a drain of the first transistor is electrically connected to the second wiring, wherein the other of the source and the drain of the first transistor is electrically connected to one of electrodes of the capacitor and a gate of the second transistor, and wherein one of a source and a drain of the second transistor is electrically connected to the first wiring.