Digital circuit Digital signal value: the string of i and o the power source or High voltage 0: the ground or Low voltage; A node in circuit can get 1 or o through switches from the power or the groundDigital circuit Digital signal value: the string of 1 and 0 1 : the power source or High voltage; 0 : the ground or Low voltage; A node in circuit can get 1 or 0 through switches from the power or the ground;