摘要 |
A particle sensor has a gain control and an offset voltage adjustment so as to provide a consistent sensor output indicative of the particle density in match with a predetermined relationship between the sensor output and the particle density, while compensating for background noises. The gain control and the offset voltage adjustment are realized respectively by digitally controllable variable resistor networks each having a plurality of switches. A memory module is included in the sensor to store instruction data for control of the switches and therefore responsible for the gain control and the offset voltage adjustment. In particular, the particle sensor includes a memory interface which enables the selective use of two types of memory means, one is an intelligent memory module composed of EEPROM and a microcomputer, and the other is a normal memory module consisting of EEPROM.
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