Design and Implementation of Low Power DSP Core with Programmable Truncated Vedic Multiplier

The programmable truncated Vedic multiplication is the method which uses Vedic multiplier and programmable truncation control bits and which reduces part of the area and power required by multipliers by only computing the most-significant bits of the product. The basic process of truncation includes physical reduction of the partial product matrix and a compensation for the reduced bits via different hardware compensation sub circuits. These results in fixed systems optimized for a given application at design time. A novel approach to truncation is proposed, where a full precision vedic multiplier is implemented, but the active section of the truncation is selected by truncation control bits dynamically at run-time. Such architecture brings together the power reduction benefits from truncated multipliers and the flexibility of reconfigurable and general purpose devices. Efficient implementation of such a multiplier is presented in a custom digital signal processor where the concept of software compensation is introduced and analyzed for different applications. Experimental results and power measurements are studied, including power measurements from both post-synthesis simulations and a fabricated IC implementation. This is the first system-level DSP core using a high speed Vedic truncated multiplier. Results demonstrate the effectiveness of the programmable truncated MAC (PTMAC) in achieving power reduction, with minimum impact on functionality for a number of applications. On comparison with the previous parallel multipliers Vedic should be much more fast and area should be reduced. Programmable truncated Vedic multiplier (PTVM) should be the basic part implemented for the arithmetic and PTMAC units.