Zener diode as a ballast. Encyclopedia of radio electronics and electrical engineering
Encyclopedia of radio electronics and electrical engineering / Surge Protectors
Comments on the article
If the voltage on the secondary winding of the network transformer is too high for the stabilizer used (Uvyp = 50 ... 100 V), and you don’t want to rewind the transformer, you usually use a ballast resistor of the appropriate rating and power, connected in series with the load. This solution is optimal for a fixed load current; if it changes significantly, instead of a resistor, it is better to use a zener diode, as shown in the figure. At currents up to 100 mA, it is convenient to use D816A, B, C, G, up to 500 mA - D815G, D, E, G. Zener diodes can be connected in series, the voltage "quenched" by them will be equal to the sum of the source of zener diodes: Uout \u1d Uvyr - EDst. An interesting feature of this inclusion is the ability to use a smoothing capacitor CXNUMX of smaller dimensions and cost, because voltage Uout is allocated on it, and not Urect.
It is only necessary to provide a current through the zener diodes of at least Istmin (10 mA for D816 and 25 mA for D815) with a resistor P1 = Uout / Istmin. If the rectifier load is non-switchable and provides this current, R1 can be omitted. The power dissipated by each zener diode P = Ust Inmax may require their installation on a heat sink. Although a pulsed current flows through VD1, when choosing a zener diode, it is permissible to focus on the output current Inmax. Similar schemes have been working for me for several years.
Author: Yuriy Karanda, Izyum, Kharkiv region; Publication: N. Bolshakov, rf.atnn.ru
See other articles Section Surge Protectors.
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 smallest ultrazoom camera
05.09.2018
Sony has unveiled the world's smallest ultrazoom camera with digital viewfinders and at least 700mm telephoto lenses. More precisely, we are talking about two models - Cyber-shot DSC-HX99 and DSC-HX95. The first is distinguished by the presence of a control ring around the lens and a touch screen with functions for focusing, releasing the shutter and changing the shooting point by touch.
The rest of the cameras are identical. Their dimensions are 102x58, 1x35,5 mm, weight - 243 g. The novelties are equipped with a powerful ZEISS Vario-Sonnar T lens with a 30x zoom (24-720 mm). Matrix - CMOS 1/2,3? Exmor R. There is optical stabilization SteadyShot. The maximum photo resolution is 4896x3672 (4:3, 18 megapixels).
The cameras will go on sale in October for €520 for the DSC-HX99 and €500 for the DSC-HX95.
|
Other interesting news:
▪ The oceans save our planet
▪ HPP801A031 - capacitive relative humidity sensor
▪ Libyan desert craters
▪ Triple Differential Receiver AD814
▪ Exercise saves chromosomes
News feed of science and technology, new electronics
Interesting materials of the Free Technical Library:
▪ section of the site Interesting facts. Selection of articles
▪ article Intraframe editing. video art
▪ article How can a malignant retinal tumor be preliminarily diagnosed from a photograph? Detailed answer
▪ article Automatic telegraph key. Radio - for beginners
▪ article Tube power amplifiers. Directory
▪ article Photo-joke. Focus Secret
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