The alarm can detect infrared rays emitted by the human body. When a person enters the monitoring area of ??the alarm, an alarm will sound. It is suitable for anti-theft alarms in important places suc'...

The circuit is shown in the figure below. This work can randomly select a number from 0 to 9; its characteristic is that during a number selection process, the digital sequence displayed by the digita'...

LM4766 is a dual-channel high-power amplifier integrated circuit launched by NS Corporation of the United States. Each channel can output 40W average power on an 8Ω load, and the distortion is less th'...

As shown in the figure, the detection alarm device circuit made of laser rod. The analog sound integrated circuit IC and other components constitute the receiving circuit. Usually, the laser emitted b'...

The micro-power remote control lighting introduced in this article is designed for disabled people with lower limb paralysis. It is simple to make, low cost, high sensitivity and stable operation. The'...

The ultrasonic anti-theft sound and light alarm consists of ultrasonic transmission, reception, time measurement, detection unit, sampling and calibration, alarm sound generation, warning light drive '...

Before making it, first have a general understanding of the characteristics of white light LED. This kit uses a straw hat head white light LED with a diameter of 5mm. The rated voltage of each LED is '...

MICRF011 is an enhanced receiver of MICRF001, suitable for keyless entry systems, security monitoring systems, remote fans, lighting control and garage door openers. Main...

As shown in the figure, this is the LM4902 audio power amplifier circuit (MSOP package). After the audio signal is input, it is coupled to the inverting input terminal (pin 4) of the amplifier through'...

Figure WS-1 is a typical circuit for electronic speed stabilization of a commonly used small DC motor. BG1 is a speed regulating tube, BG2 is a comparison amplifier tube, and the comparison voltage is'...

The circuit consists of Q2, R3, C3, etc. When the power is just turned on, C3 is equivalent to a short circuit, and the power is connected to the ground through R3, Q2's be junction, and C3. Q2 is sat'...

Automotive OEMs are migrating to BLDC to maximize efficiency and reliability. This article looks at the important parameters engineers should consider during the design process to achieve these goals.

The treble is 15W, and this ratio must be used for overall design, and the insertion loss of the RC filter and the gain of the amplifier must be adjusted to achieve balance in the entire system. For a'...

The figure below shows the connection diagram of the 51 series single-chip microcomputer 89C2O5l and MAX7219. For convenience, only one common cathode digital tube U3 is drawn in the figure. The other'...

This solution is an FPGA-based binary clock that uses GPS as a time reference.

The circuit is very simple. Use a common 555 timer connected in oscillator mode. The heater can be connected in parallel with up to 5 10W heating wire elements HC1~HC5. So the maximum power of the hea'...

Working principle: +24V voltage passes through diode VD1 and then is filtered by capacitor C1 to form a stable DC voltage. This voltage is added to the base of transistor V1 through resistors R1 and R'...

CSJ-R05B is an industrial-grade superheterodyne miniature receiving component. It is based on the CSJ-R05A component and adds a surface acoustic wave resonator frequency-stabilized local oscillator an'...

This small fast charger can charge two AA or AA batteries at the same time. It is equipped with a charging indicator light to indicate the charging status. When the battery power is low, the indicator'...

In this circuit, choose 10Ω for R1 and 200Ω for R2. When the switch is closed upward, the charging current is 60mA (constant current); when the switch is closed downward, the charging current is 3mA ('...