A Method To Reduce Power Consumption Of Embedded Fingerprint Identification System And Its Application

A digital image processing method has been used by the Automated FingerprintIdentification System (AFIS) to realize the function of identification. TraditionalEmbedded AFISs are commonly using DSPs that have high speed data processingability or ARM series MCUs that have high performance. Consequently, the powerconsumption of the whole system is inevitably restricted to a high level, whichseriously limit the continuous working times in battery-powered systems.In this paper, a Duo-Core architecture system is introduced to solve thecontradiction of high performance and low power consumption. One control core,ML67Q5250, accomplishes the work of realizing the function of collecting,processing, recognizing and matching of the fingerprint image, while the othercontrol core, MSP430F149, realizes the function of controlling all the peripheral unitsand regulating the power supply of the ML67Q5250unit to minimize its workingtime. Thus, the power consumption of the whole system can be reduced.The works of this paper are mainly focused on the following parts:An embedded fingerprint identification module has been designed, which canwork independently and also be able to co-works with the other MCUs. Furthermore,an integrated interface has been devised, which is compatible with3differentfingerprint sensors respectively.A peripheral control module has been designed based on MSP430F149, whichincludes a keypad input unit, a interactive menu display system, a data storage unit, acalendar function unit, and a motor drive unit. Additionally, this MSP430F149peripheral control module can work as an electronic password function independently,which has super low power consumption.Tests have been performed, and the results show that the system standby currentcan be reduced to5~6μA, which indicates that the system can work continuously formore than3years with the power of one common5#dry cell.