Understanding Smart Sensors - Nomads.usp

Using MCUs/DSPs to Increase Sensor IQ 115Table 5.3Theoretical Relative Die Costs for Sensor IntegrationBest inClass*Typical MOSIndustry*Expected Level of Sensor ProcessDevelopmentDefects/cm 2 0.2 0.8 2.0 4.0Die size (inches)0.100 by 0.100 1.01 1.05 1.14 1.290.128 by 0.128 1.70 1.81 2.05 2.500.300 by 0.300 10.85 15.15 27.69 65.110.311 by 0.311 11.31 16.17 30.89 75.28*Theoretical 6-inch wafers. Die cost of 1.0 for 0.100 by 0.100 die and zero defects/cm 2 .An interim approach to the fully integrated sensor on an MCU is shownin Figure 5.11. The sensor interface for the accelerometer is initially a standalonecircuit that uses the same design rules and process as the MCU. ThatG-cell with self-testHCMOS control ASICSwitchedcapacitorintegratorS/HamplifierLow passfilterTemp.controlCANPORTMRSCISPIHCMOSMCUCPURAMROMROM68HC05C4ROMFigure 5.11 Two-chip sensor and HCMOS sensor interface IC.