YJJ SGX-4CO small volume long life carbon monoxide gas sensor is used for consumer smoke gas detectors

Product Description:

SGX-4CO small volume long life carbon monoxide gas sensor is used for consumer smoke gas detectors

Features:

SGX specializes in the development and production of air quality sensors, the SGX-4COis a small-size, long-life carbon monoxide gas sensor suitable for consumer smoke gas detector applications.

The electrochemical gas sensor needs to provide a stable bias between the Sensing electrode and the Reference electrode. The voltage of the Reference electrode is controlled by the Counter electrode, so the bias is generally stabilized by controlling the Counter electrode with the op amp. The sensor is a current output, although the current size is proportional to the gas concentration but the value is very small, so a mutual resistance amplifier is needed to provide current amplification and convert voltage to the MCU and other processing units. The amplifier circuit often also needs to achieve zero setting and magnification times, and the voltage output representing the gas concentration also needs to collect temperature and pressure information to compensate.

The SGX-4CO has a bias voltage Vref of 0, and the op amp U1.2 controls the Counter electrode to keep the bias constant at 0. R2's 10-ohm resistance and the equivalent capacitance inside the sensor form an RC oscillation circuit to improve sensor response time. R3 resistance control amplification, the current sensitivity of SGX-4CO is 30nA/ppm, so the circuit output sensitivity is 25K*30nA/ppm=0.75mV/ppm, pay attention to the output sensitivity multiplied by the maximum measurement range of 500ppm cannot exceed 1.3V, otherwise the output can not cover the whole measurement range.

Specifications:

long life carbon monoxide gas sensor

small volume carbon monoxide gas sensor

YJJ SGX-4CO small volume long life carbon monoxide gas sensor is used for consumer smoke gas detectors Images