Hardware Overhead Reduction of a QDI Booth Multiplier

This paper presents a new method to implement a multiplier using the Quasi Delay Insensitive (QDI) approach. QDI circuits allow unbounded delays on wires and gates, and require the difference among the delays in forks to be less than the delays of their terminating gates. To implement the Booth multiplier following the QDI approach, we considered Martin’s method. In this method, an asynchronous circuit is considered as a set of cells that communicate through a handshaking protocol, and is synthesized from a high level definition through different levels of translation. The main problem related to the resulting circuits their considerable overhead due to the implementation of handshaking protocols. In our proposed method, the overhead is reduced 50% by separating the control and data path units. This solution increases the forks, and causes complexity in physical implementation. By applying some of the rules derived from Martin’s method, the forks became locally limited to ease up the physical implementation.