Signal detection and processing circuit

Test - lowercase jpg

Kaixin micro test

Test probe P100-M3

Industrial Router Crystal 3.2*2.5mm 3225 26M (26.000MHZ) 12PF 10PPM 20PPM 30PPM

The following figure shows the signal detection and processing circuit consisting of red pyroelectric infrared sensor, photoresistor and BISS0001. The red pyroelectric infrared sensor is sensitive only to infrared radiation having a wavelength of about 10 μm (the wavelength of the human body's radiation infrared rays), so that objects other than the human body do not cause the probe to operate. The probe contains two pyroelectric elements connected in series or in parallel, and the two electrodes are made in the opposite direction. The environmental background radiation has almost the same effect on the two pyrolysis elements, so that the discharge effects cancel each other out. Therefore, the detector has no signal output. Once a person invades the detection area, the infrared radiation of the human body is partially focused by the mirror and received by the pyroelectric element, but the two pieces of pyroelectric elements receive different amounts of heat, and the pyroelectric power is different, and cannot be cancelled, so the detection signal is output. BISS0001 is a digital-analog hybrid ASIC composed of an operational amplifier, a voltage comparator, a state controller, a delay time timer, and a lock-up timer. When the external light intensity is strong, the resistance of the photoresistor is small, and BISS0001 detects a low level, thereby blocking the 14-pin and prohibiting the signal of the sensor infare1. When the external light intensity is weak, the photoresistor has a large resistance value. BISS0001 detects a low level and turns on 14 feet. When infarre1 detects the human body signal, it produces a weak signal output through R5, R1005, R4, C1, C6. A signal amplification filter circuit composed of C7. Delay circuit composed of R1000, R1001, C1000 and C1001. The signal is processed and output from pin 2.