Using the X-FAB 1μm SOI-CMOS process, a 50pF
capacitor constructed in a poly1-met1-met2-met3 structure,
requires an area of about 0.32mm2. Compared with the
conventional 1μF blocking capacitor, the capacitance is 20000
times smaller. Fig. 7 shows the layout of a two-channel
stimulator output stage using the proposed circuit. The X×Y
silicon area is 1.25×0.8mm2.