A 16-bit Carry Look-ahead Adder was designed for use in the accumulator section of the filter. This adder is composed of four 4-bit carry-look-ahead (CLA) adders and has two 16-bit input lines labeled A and B. The carry output of each section ripples from module to module, as shown in Figure 1.

Figure 1: 16-bit Adder Design

The full implementation of the adder is shown in Figure 2.

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Figure 2: 16-bit Adder Implementation

An IRSIM simulation of the adder was performed to verify its functionality. The results of this simulation are shown in Figure 3.

Figure 3: 16-bit Adder Simulation

The longest delay of this adder was found to be along the carry bits. For more information, please refer to the Crystal/SPICE section of the report.