A design for low power CMOS system-on-a-chip mixed signal wireless sensor devices.
The concept is used in devices to monitor vibration, audio, radiation or other signals, for which low power usage is important. Such applications can include wireless vibration sensors in mechanical equipment to detect a bad bearing or other machine fault, or for intrusion detection in a security system.
This concept extends battery life by enabling a ?sentry mode? continuous monitoring of the signal at very low power consumption, on the order of nano-watts. Once a signal is detected, a ?high resolution mode? is activated with an analog to digital converter and digital signal processor to provide an accurate analysis for verification. The single chip contains the analog sensing circuit, a digital processor and a communication unit for wired or wireless links.
These sensors can provide around-the-clock monitoring at 1/1000th the power of existing sensors, extending the lifetime of battery-powered wireless sensors to years rather than weeks or months. The single chip design reduces the size of the sensor device facilitating its installation and dramatically reduces the cost of the wireless sensor device.