Smoke detector with aspiration unit and flow sensor

摘要

A detector includes a smoke sensor and an aspiration unit. The aspiration unit causes ambient air from a region directly adjacent to the detector to flow into a sensing region of the sensor. A flow monitoring sensor provides feedback to a control circuit to vary pulse modulated drive signals coupled to the aspiration unit. A plurality of variable resistance temperature sensors can be used for flow monitoring. Communication with the detector can be carried out via interface circuits.