cell with this formula the or u2212 state difference in outputs 0 and 0_b can be determined based on the or u2212 state difference between each of the inputs x u2212 x_b and y u2212 y_b as illustrated in the following table a from table a it can be see that o u2212 o_b x u2212 _b when y u2212 y_b is also from the table it can be seen that o u2212 o_b x_b u2212 x when y u2212 y_b is u2212 thus with x and y as inputs and x_b and y_b grounded y will be inverted as the output o_b with x being and y will not be inverted as the output o_b with x being u2212 this is illustrated in table b as follows fig1 b thus illustrates how the x and y input terminals and the o_b output terminal of the gilbert cell 1000 can be connected to form an exor gate with the x_b and y_b inputs to the gilbert cell 1000 connected to ground as shown in fig1 a they are not used in the exor gate of fig1 b leaving x and y as inputs with o_b selected as an output the following truth table table c is provided for.