How to use the least amount of money to make a good-sounding speaker has always been the goal pursued by "welder" enthusiasts. Recently, the author spent three or four hundred yuan to make a set of sp'...

The circuit of this design is shown in the attached figure. It uses IC1 (74HC4046PLI. Phase-locked loop) integrated circuit chip with an operating frequency of 1MHz to improve the noise resistance of '...

Close the three-phase air switch, the intermediate relay is energized. Press the K2 normally open button, K2 is self-locked, and the AC contactor K is closed. If phase A is missing due to a fault, the'...

The design of this reminder circuit was inspired by the pet dog at home, which starts barking continuously when it detects a moving shadow. Dogs have the ability to adaptively increase their visual se'...

The following figure is a circuit that simulates the sound of a chicken. When a handicraft pompom chicken is equipped with this circuit, it will become lifelike and more attractive. If it is placed in'...

NE5532/SE5532/SA5532/NE5532A/SE5532A/SA5532A is a dual op amp high performance low noise operational amplifier. This device is particularly suitable for applications in high quality and professional a'...

A pulse frequency doubling circuit can be formed by using a CD4013 and a 4:12 input NOR gate CD4001. The circuit composition is shown in the figure.

When the vehicle brakes, the driver presses the brake switch and the brake lights light up immediately. After releasing the brake switch, the brake lights go out immediately. If the brake lights can b'...

OPA660 is a general-purpose integrated circuit designed for broadband systems, including high-performance video, RF, and IF circuits. OPA660 contains a broadband bipolar voltage-controlled current sou'...

The touch dimmer shown in the figure uses a "parametric solid-state relay" (PSSR) as the main control element instead of the commonly used bidirectional thyristor. The dimming process uses touch...

In permanent magnet synchronous motor control, whether it is sensored FOC or sensorless FOC, obtaining accurate motor parameters can improve the performance of the controller and observer.

This article introduces the principles and design of active discharge circuits and explains the selection criteria for key components such as power MOSFETs to ensure repeatable performance and reliabi'...

The main circuit of the whole machine is the common single-chip FM stereo broadcast transmitter integrated circuit BA1404, which has a very mature circuit. In order to facilitate beginners to make the'...

The principle wiring of three-stage zero-sequence current protection is shown in the figure below. Current transformers with exactly the same model and transformation ratio are installed on the three '...

The interface circuit between MMA1220D and microcontroller is shown in the figure below. The microcontroller can be a single-chip microcomputer with A/D converter, such as ADμC8xx series. The status t'...

The F/V conversion circuit composed of AD650 is shown in the figure below. Its output voltage is VOUTAVG=tOS×RINT×a×fIN. In the formula, fIN is the input frequency, a is the current source value (for '...

This simple circuit can sound an alarm when the AC power is off (or the voltage is less than 50V). The alarm is easy to test. After installation, plug in the AC power and the buzzer should be silent. '...

10 Examples of Classic Rectification Circuits

The structure of a series DC regulated power supply is shown in the figure below (a). It can be seen that a series DC regulated power supply usually consists of six parts: transformer, rectifier filte'...

The movements that use SANYO 80P switching power supply include: SANYO CTP-3515, CTP-3525, CYP3915, CTP6916, CTP6921, CTO3227, Kunlun S371, Shanghai Z651-1 and Kangyi color TV, etc.