Arithmetic unit for processing guard bits simply in DSP and guard bits processing method in the Arithmetic unit

摘要

PURPOSE: A device for simply operating a guard bit on a DSP(Digital Signal Processor) and a method for processing the guard bit on the same are provided to reduce cost by reducing a circuit for processing the guard bit of an operator and reducing the number of the used devices. CONSTITUTION: The operator(20) outputs an addition result of 'n' bit through an addition operation by receiving the first and the second input of the 'n' bit. An accumulator(30) of the 'n' bit accumulates the output of the operator(20). A guard bit processor(40) compares respective code bit by inputting the first and the second input upper than 'p', and the upper 'p' bit of the operator's output, and processes the guard bit by adding or subtracting 1 to a current guard bit value according to a comparison result.