New Technology for Air Quality Monitors and Smoke Detectors

fish001

New Technology for Air Quality Monitors and Smoke Detectors [Copy link]

Air quality sensors are not new. In fact, we all have one on our face. Unfortunately, our noses are sometimes unreliable, failing to detect odorless harmful gases or when a fire breaks out nearby while we are asleep. Microcontroller-based air quality sensors and smoke detectors have also been around for a while, but now a new generation of low-power, highly integrated, high-performance microcontrollers are being combined with ultra-sensitive sensors to detect the faintest particles of harmful gases or smoke in homes, offices, construction sites, and anywhere else. For many applications, such as smoke detectors, these new microcontrollers are basically a chip detector minus the light tube. The high level of integration of these microcontrollers makes them a very cost-effective solution for other applications that require the connection of specialized sensors to detect specific gases such as carbon monoxide. Many microcontrollers have integrated memory resources, but few have unified, monolithic memory blocks to avoid the limitations of a “RAM and Flash” architecture. The FRAM (Ferroelectric Random Access Memory)-based memory architecture provides developers with more flexibility and configurability, simplifying the way to adapt applications to this platform. For example, instead of having more Flash space and less RAM space, system designers can configure the memory to meet the needs of the application, rather than having to squeeze the application into a memory architecture dominated by available memory modules. Some applications may require more memory space to store data logs to track when gas concentrations exceed a certain threshold. Such a detector may need to allocate more of the available memory space to Flash equivalent storage and less to RAM storage to store the program. For other applications, the allocation ratio may be reversed. With a unified memory architecture, developers can easily reconfigure the memory to meet the needs of the application. This flexibility of integrated memory has another advantage, which is higher integration, reducing bill of materials (BOM) costs and board space. In addition to eliminating external memory devices, some new generations of highly integrated microcontrollers use analog front-end components such as external oscillators and operational amplifiers. Some new microcontrollers even use ultra-sensitive transimpedance amplifiers (TIAs) that can perform monitoring and convert small current signals into voltage signals. Up to six discrete chips can be removed from the original design, and the size of the circuit board can be reduced by 75%. All of the above features make for a very cost-effective new product design.

Of course, the high level of system integration also affects the reliability and power consumption of the system. The reduction in external components simplifies assembly and reduces manufacturing costs.

Many residential, industrial, and commercial air quality sensors are not connected to the power grid and are powered by small batteries such as button cells or AA batteries. Therefore, low power consumption is a priority because it affects the battery replacement cycle of the sensor. In most cases, the longer the battery life, the better it is for the user. Homeowners may want to install smoke detectors that don’t need to have their batteries replaced for 10 years or more. In industrial environments such as factory production lines, gas detectors may be installed in difficult-to-reach or dangerous locations. Reducing the time between replacement batteries can reduce production line downtime for maintenance, increasing production line efficiency and yield. Interestingly, low power also helps detectors that are not powered by batteries or wires to use more power modes in a network, increasing the ability to cope with limited power sources. Another issue to consider in some cases is communication support, as many applications air quality detectors are part of factory automation or building maintenance systems. Standard I/O interfaces such as SPI, I2C, and UART can connect directly to wired networks or to wireless technologies such as Wi-Fi or Bluetooth.

alan000345

Good information, thanks for sharing.