Analogue EHW Chip for Intermediate Frequency Filters

This paper describes an analogue EHW (Evolvable Hardware) chip for Intermediate Frequency (IF) lters, which are widely used in cellular phones. When analogue Integrated Circuits (ICs) and LargeScale Integrated Circuits (LSIs) are manufactured, the values of the analogue circuit components, such as resistors or capacitors, often vary from the precise design speci cations. Analogue LSIs with such defective components can not perform at required levels and thus have to be discarded. However, the chip proposed in this paper can correct these discrepancies in the values of analogue circuit components by genetic algorithms (GAs). Simulations have shown that 95% of the chips can be adjusted to satisfy the speci cations of the IF lters. Using this analogue EHW chip has two advantages, namely, (1) improved yield rates and (2) smaller circuits, which can lead to cost reductions and e cient implementation of LSIs. The chip is scheduled to appear in the fourth quarter of 1998.