USB port - switch. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Computers
Comments on the article
Currently, almost all personal computers are equipped with USB ports for communication with peripheral equipment. It comes to curiosities - on the Internet you can find messages about USB soldering irons, USB vacuum cleaners and USB lamps. Judging by the information provided, these devices are not so much controlled from the USB port as they are powered from it with a constant voltage of +5 V.
In my opinion, such a stupid use of the resources of the power source of a personal computer can hardly be called justified. And yet, it may be desirable to have some devices or components of your laboratory equipment turned on and off at the same time as the personal computer is turned on or off.
In the text I will give a diagram of two simple devices that consume relatively little power from a computer power source via a USB port and connect the load to the mains at the same time as the personal computer is turned on. There is no software here - pure electronics. When the computer is turned on, its source switches from standby (or off) to online mode. A voltage of +5 V appears, which is supplied to the 1st and 4th pins of the USB connector. From these contacts, the LED of the optocoupler is powered, which turns on the load.
In the circuit in Figure 1, the optocoupler is low-power, so triac U2 is used to turn on the load.
The circuit shown in the figure is simpler, it uses a powerful opto-triac U1, which can drive a load up to 1kW directly.
A third option is also possible, in which the functions of the load switch will be assigned to an electromagnetic relay with a 5 V winding. In this case, you must not forget to connect a reverse voltage diode in parallel with the relay winding (so that the induction surge does not damage the port).
Author: Anufriev K.N.
See other articles Section Computers.
Read and write useful comments on this article.
<< Back
Latest news of science and technology, new electronics:
Artificial leather for touch emulation
15.04.2024
In a modern technology world where distance is becoming increasingly commonplace, maintaining connection and a sense of closeness is important. Recent developments in artificial skin by German scientists from Saarland University represent a new era in virtual interactions. German researchers from Saarland University have developed ultra-thin films that can transmit the sensation of touch over a distance. This cutting-edge technology provides new opportunities for virtual communication, especially for those who find themselves far from their loved ones. The ultra-thin films developed by the researchers, just 50 micrometers thick, can be integrated into textiles and worn like a second skin. These films act as sensors that recognize tactile signals from mom or dad, and as actuators that transmit these movements to the baby. Parents' touch to the fabric activates sensors that react to pressure and deform the ultra-thin film. This ... >>
Petgugu Global cat litter
15.04.2024
Taking care of pets can often be a challenge, especially when it comes to keeping your home clean. A new interesting solution from the Petgugu Global startup has been presented, which will make life easier for cat owners and help them keep their home perfectly clean and tidy. Startup Petgugu Global has unveiled a unique cat toilet that can automatically flush feces, keeping your home clean and fresh. This innovative device is equipped with various smart sensors that monitor your pet's toilet activity and activate to automatically clean after use. The device connects to the sewer system and ensures efficient waste removal without the need for intervention from the owner. Additionally, the toilet has a large flushable storage capacity, making it ideal for multi-cat households. The Petgugu cat litter bowl is designed for use with water-soluble litters and offers a range of additional ... >>
The attractiveness of caring men
14.04.2024
The stereotype that women prefer "bad boys" has long been widespread. However, recent research conducted by British scientists from Monash University offers a new perspective on this issue. They looked at how women responded to men's emotional responsibility and willingness to help others. The study's findings could change our understanding of what makes men attractive to women. A study conducted by scientists from Monash University leads to new findings about men's attractiveness to women. In the experiment, women were shown photographs of men with brief stories about their behavior in various situations, including their reaction to an encounter with a homeless person. Some of the men ignored the homeless man, while others helped him, such as buying him food. A study found that men who showed empathy and kindness were more attractive to women compared to men who showed empathy and kindness. ... >>
| Random news from the Archive The ultrasonic sticker will allow you to see through the skin.
24.02.2024
Engineers from the Massachusetts Institute of Technology (MIT) have developed a revolutionary ultrasound sticker to track the health of patients' internal organs. This small device, about the size of a postage stamp, is attached to the skin and allows you to monitor the condition of internal organs, identifying signs of diseases such as liver or kidney failure, and also monitor the development of tumors.
The new product is capable of directing ultrasonic waves through the skin, reflecting from internal organs and returning to the sticker.
"When some organs are diseased, they can become harder," said MIT mechanical engineering professor Xuanhe Zhao.
The ultrasound patch can continuously monitor organ stiffness for 48 hours, with sufficient sensitivity to detect minute changes that indicate disease progression. For example, when tested on rats, the sensor quickly detected early signs of acute liver failure.
"Immediately after a liver or kidney transplant, we can attach this sticker to the patient and observe how the organ's stiffness changes over several days," says the study's lead author, Hsiao-Chuan Liu.
To measure the stiffness of organs such as the kidneys and liver, clinicians typically use ultrasound elastography, which requires specialized equipment. Successful experiments on rats have already been carried out. The next step will be to work with physicians to tailor the sticker to the needs of transplant intensive care unit patients.
The development of the ultrasound patch represents a significant advance in the medical field, providing continuous monitoring of internal organs without the need for specialized equipment. The new device has the potential to significantly improve the diagnosis and monitoring of patient health.
|
Other interesting news:
▪ Perception of color changes with the seasons
▪ iPhone predicts the desires of the owner
▪ Fish evolve from anglers
▪ HDD TV from Sanyo
▪ LG CordZero HOM-BOT Turbo+ AR Robot Vacuum Cleaner
News feed of science and technology, new electronics
Interesting materials of the Free Technical Library:
▪ section of the site Audio and video surveillance. Selection of articles
▪ article by Roger Bacon. Famous aphorisms
▪ article Who is Messalina? Detailed answer
▪ article Deren bloody. Legends, cultivation, methods of application
▪ article Welding inverter. Encyclopedia of radio electronics and electrical engineering
▪ article Mains voltage deviation indicator. Encyclopedia of radio electronics and electrical engineering
Leave your comment on this article:
All languages of this page
Home page | Library | Articles | Website map | Site Reviews
www.diagram.com.ua
2000-2024
Arabic
Bengali
Chinese
English
French
German
Hebrew
Hindi
Italian
Japanese
Korean
Malay
Polish
Portuguese
Spanish
Turkish
Ukrainian
Vietnamese