Gate Arrays:CMOS Gate Arrays.

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CMOS Gate Arrays

CMOS gate arrays are commercially available from many manufacturers in slightly different layout forms. As an example, Figure 46.2 shows a cell of a CMOS gate array, where a pair of pMOSFETs and a pair of nMOSFETs are placed on the left and right, respectively, without connections between them. The NAND gate shown in Figure 46.3(a) can be realized by connecting the components shown in Figure 46.2 by two metal layers as shown in Figure 46.3(b). These two metal layers are formed by forming the first metal layer shown in Figure 46.3(c), the insulation layer (not shown), and then the second metal layer shown in (d). The inverter shown in Figure 46.4(a) can be realized by connections as shown in Figure 46.4(b).

Many different patterns other than that in Figure 46.2 are available for the components of a cell.

Gate Arrays-0517

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