Infrared pyrolysis control module based on QXRS012

QXRS012 is a device that can be used with an infrared sensor unit to achieve simple sensing ON/OFF and delay function control of the load; at the same time, the chip has a built-in high-precision and stable LDO 3.0V output that can provide power for the infrared sensor; a built-in one-level high-gain fixed A 30dB amplifier, combined with a peripherally adjustable second-order bandpass filter amplifier, can achieve a high-reliability infrared human body sensing signal processing chip that can amplify up to 75dB low-frequency bandpass signals.
Chip Features Working voltage: 2.8-5.5V 
Low standby power consumption: 18-22uA (very suitable for battery applications); 
built-in LDO output voltage 3.0V @max 5mA can directly power the PIR; 
fixed 2S internal blocking time simplifies peripherals and suppresses interference ; 
Light control enable function (photoresistor); 
Delay time is adjustable with a single external capacitor; 
Built-in first-level amplifier, the number of peripheral components can be simplified to less than 8; 
Simple peripheral PCB layout can be completed with a single panel, low cost; 
Continuous, Discontinuous two-trigger mode chip classification is optional. 
Practical applications are very suitable for simple peripheral battery-based applications. LED lighting sensor lights (solar lithium battery triangular wall lights, dry cell sensor night lights, battery sensor corridor lights, etc.); 
various types of automatic lighting fixtures, Automatic sensor switch application systems for automatic doors, wash basins, dryers, alarms, etc.; 
circuit applications related to human body infrared and microwave sensor switch signal processing; 
IC package pin functions and electrical characteristics

(1) Pin function

Circuit diagram

Application Guide (1) Amplification circuit parameter setting: It can be seen from the internal block diagram of the QXRS012 specification that it has a built-in wideband gain amplifier (second-stage amplification circuit) with a gain of about 30dB, and the peripheral components R2, R4, and C3 The first-stage bandpass filter amplifier circuit composed of , C4 is provided for users to make corresponding adjustments according to needs. For details on the adjustment methods and methods of the specific parameters, please refer to the content in "Amplification Circuit" on page 6 of our QXRS012 specification book. and calculation formulas. Our company recommends that the FL and FH of the first-stage amplifier be set and controlled between 0.1HZ and 10HZ respectively, with the 1HZ frequency as the maximum gain setting of the center frequency, while maintaining the total gain GA (the first-stage amplification factor G1=20LOG(R4 /R2)+second-stage amplification (30dB)) is controlled between 65-75dB, because if the GA is too large, external interference signals will enter the amplifier and cause false triggering. Adjust R2, R4, C3, and C4 appropriately according to the customer's actual application circuit. Combination (the value of C4 is not recommended to be too small, it is recommended to be between 4.7-47uF) solution to achieve the application conditions that meet the frequency band and gain suitable for the normal operation of the normal sensing circuit module of the human body.