No COVID19 Wave- Its a EEENOTES2U Traffic Waves

 Please do not be perplexed. COVID19 Waves aren't depicted in the image. Website Traffic Waves are the name of the game here.

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    Blogging is a terrific method to show off your skills and hobbies to potential employers while also giving your resume an edge. When you write regularly, it demonstrates your commitment, enthusiasm, and originality, all of which are desirable qualities in job applicants.

    When you start blogging, the first thing you discover is that people can leave you with a single click. So you have to get to the point quickly; you can't waste people's time; you have to give them something in exchange for their limited attention span.

    “Don’t focus on having a great blog. Focus on producing a blog that’s great for your readers.”

#EEENOTES2U- https://sites.google.com/site/eeenotes2u/

#SPOTTURNS- http://spotturns.blogspot.com/

Is really the rotation of the Earth unexpectedly slows down? If Yes what are the consequences?

In recent days, there is a big debate is going on among the researches and scientists about EARTH ROTATION? i.e., global warming, and other constructions actually slowdowns the earth claimed by some. Simultaneously other is put an argument that global warming is increasing the earth spin faster.

After seeing these all arguments, I had started analyzing the concept with my curiosity. It ends me to stand the side of the people who argued that global warming and other constructions on earth really slowdowns the earth spin rather than increasing it.

My Explanation for supporting the earth spin is slowing down by global warming and other big constructions made on the earth is as follows

The Earth rotates around its axis once a day, but it does not rotate evenly. The rotation rates then differ by up to one milliseconds per day. The speed of Earth's rotation would increase like a spinning ice skater whose rotary speed is increased as the skater's arms are brought closer to her body, if her mass comes closer to her axis of rotation, as it is shown in Figure. 1. Conversely, if the mass is shifted away from the rotating pole, the speed of rotation on the planet will be slow down as shown in Figure. 2.

Figure.1 Skaters spinning principle

Figure. 2 Earth Spinning View

To support my statement, I have chosen two examples.

Firstly, if all of Earth's ice melts and flows into the ocean, what would happen to the planet's rotation? 

Melting land ice including mountain glaciers and ice sheets of Greenland and Antarctica can only change the rotation of the Planet if the meltwater falls into the oceans. If the meltwater stays close to its source (for example, by being trapped in a glacier lake), so there will be no net mass transfer away from the glacier or ice sheet, and the rotation of the Planet does not change. So, if the meltwater flows into the oceans and is absorbed, then a net mass migration happens and the motion of the Planet will change. For example, if the Greenland ice sheet were to melt completely and the meltwater drained entirely into the oceans, then the global sea level would increase by about seven meters (23 feet) and the Earth would spin more slowly, with the length of the day being longer than it is now, by about two milliseconds.

Figure. 3 Antarctica distance from earth spinning axis

Figure. 4 Ice melting in Antarctica

Secondly, if you build a big dam and store water in it, construct big buildings and populated with huge people, etc., what will happen to earth rotation?
I have taken china’s biggest dam as an example

Three Gorges Dam, China crosses the Yangtze River in Hubei province, China. It the world's largest hydroelectric power station by total capacity, which will be 22,500 MW when completed. When the water level is maximum at 175 meters (574 ft) over sea level (91 meters (299 ft) above river level), the reservoir created by the dam is about 660 kilometers (410 mi) in length and 1.12 kilometers (0.70 mi) in width on average. The total surface area of the reservoir is 1045 square kilometers, and it will flood a total area of 632 square kilometers, of land. The reservoir will contain about 39.3 cu km (9.43 cubic miles) of water. That water will weigh more than 39 trillion kilograms (42 billion tons). 

Figure. 5 China’s largest dam 

A change in a mass of this magnitude will impact the Earth's rotation due to a phenomenon known as the moment of inertia, which is a solid rotating body's inertia with respect to its movement. The object's moment of inertia over a given axis defines how difficult it is to adjust its angular motion along that axis. The longer a mass's distance to its rotational axis, the slower it can spin. You may not know why, but in daily life, you see examples of that. For example, a figure skater attempting to spin more rapidly would draw her arms close to her bodies, thus reducing her moment of inertia. Likewise, a diver who wants to somersault faster can get his body in a tucked spot. 

Through lifting 39 trillion kilograms of water 175 meters above sea level, the Earth's moment of inertia will increase and thus slow its rotation. But the impact will be incredibly small. NASA scientists determined that moving this as the mass would only increase the duration of the day by 0.06 microseconds, rendering the Planet in the middle and flat on top just slightly more circular. The pole position will be moved by about two centimeters (0.8 inches).

Figure. 6 China’s largest dam slowdowns the earth's spinning.

The source of the above knowledge drives me to think in such a way that, whether the slow spinning of the earth will really affect the earth's gravity? As I am keen to learn these kinds of info, I am posting my view in Infront of readers. Please excuse me if I am wrong.

From starting I strongly believe the concepts of antigravity in ancient times, where they have used sound, mass, time at which planets are in particular distance from the object to vary the effective value of earth gravity on the particular object. That allows them to construct megalithic. For more details, U can visit my previous articles [5], [6]. However, I could not able to prove the concept mathematically in that time, and here I am keeping my view on this regard. As given in Appendix A, the mass movement away from the earth spinning axis leads to a higher value of gravity forcing on the object. Which may cause major earthquakes [reference source Figure. 7]. On the other hand, the slowing down of earth spinning may cause the imbalance in the earth's orbital axis, which further leads to the collapse of the earth on to the sun.

Figure. 7 News Paper Report about Earth spinning slowdown and their consequences

Appendix A: Derivation of Effective Value of Earth Gravity on Any Object

Outward centrifugal force caused due to the rotation of earth effects (decreases) the acceleration due to gravity. The change varies with the latitude.
Let us consider the earth to be a spherical ball of mass ‘M’ and radius ‘R’. An object of mass ‘m’ is at point P at latitude φ, when the earth is not rotating the weight of the object is mg. But earth is rotating with angular velocity. So, the object is moving in a circular path of radius ‘r’ as shown in the figure. The object experiences a centrifugal force,

                     (1)

The object is being acted by two forces ‘mg’ and ‘Ff‘. The resultant of these two forces gives the apparent weight of the object (mg). The resultant of the two forces is given by the diagonal of the parallelogram OPAB.

From parallelogram law of vector addition:

The value of ω is 7.2921159 × 10−510−5. So, the term containing ω^4 is much smaller than 1 and ω^2 so can be neglected

 

At poles; φ = 90°
g’ = g.
So, at the equator, the effect is highest so the gravity is lowest and at the pole’s gravity remains unaffected of rotation.

References:

[1]    https://climate.nasa.gov/faq/30/if-all-of-earths-ice-melts-and-flows-into-the-ocean-what-would-happen-to-the-planets-rotation/ 

[2]    https://www.forbes.com/sites/trevornace/2017/11/20/earths-rotation-is-mysteriously-slowing-down-experts-predict-uptick-in-2018-earthquakes/#29b263f66f24 

[3]    https://www.climatedepot.com/2019/07/24/settled-science-nasa-claims-earths-rotation-is-slowing-due-to-moon-but-harvard-study-claimed-earth-spin-faster-due-to-global-warming/ 

[4]    https://www.kinetica.co.uk/2014/03/27/chinese-dam-slows-down-earths-rotation/ 

[5]    https://spotturns.blogspot.com/2016/09/unexplained-ancient-achievements-anti.html

[6]    https://spotturns.blogspot.com/2016/04/gravity-and-antigravity.html

Earthing Restores the EM Fields in the Body

Earthing Restores the EM Fields in the Body | Earthing Science (Entrainment) and Health Effects: Earthing can reduce inflammation and Produces Unique Electrical Function In Brain & Muscles

Earthing is a truly groundbreaking rediscovery. One of the many pieces of data that help us understand the relationship between our bodies and the Earth.

In Dan Winter's epic video Series, he reviews the Science of Coherent Entrainment. We discussed this in detail in the post Science of Intentional Healing | Scientists Observe Brain Cells While Healing Intention Is Directed Towards Them – Here’s What Happened and Precognition Explained: Science Shows How Our Body Reacts To Events Up To 10 Seconds Before They Happen. Entrainment is the phenomenon whereby a greater system imprints itself onto a lesser one, creating a new system which connects the two.

Our bodies use EM Fields (auric fields) which are synchronized with the Earth's fields. The more our bodies are able to access these stabilizing and health-imparting fields the greater our health and vitality are.

Let's consider the ability of the human voice to shatter a wine glass, which reveals how entrainment works. The wine glass has a resonant frequency, which is dependent on the material it is made of and the geometry (shape) of the glass itself. When the singer emits a pitch which matches the same resonant frequency as the glass, it begins to vibrate because the waves being received are at the same frequency of the resonant signature of the glass. The singer increases the volume of their voice, which adds energy in the form of increased amplitude of the vocalized frequency, received by the glass. The glass shatters because the amount of energy received causes vibrations in the glass which overwhelm the stability of the crystalline structure it is made of, causing it to 'shake itself to pieces.'

Source:http://www.stillnessinthestorm.com

What are Seed Balls?

What are seed balls and seed bombs?

A seed ball (or seed bomb) is a seed that has been wrapped in soil materials, usually a mixture of clay and compost, and then dried. Essentially, the seed is ‘pre-planted’ and can be sown by depositing the seed ball anywhere suitable for the species, keeping the seed safely until the proper germination window arises. Seed balls are an easy and sustainable way to cultivate plants in a way that provides a larger window of time when the sowing can occur. They also are a convenient dispersal mechanism for guerrilla gardeners and people with achy backs.

A pile of seed balls.

History 

Seed balls may have been used by the Ancient Egyptians to seed the receding banks of The Nile after annual floods. They have been used in Asia and elsewhere, especially in arid regions, because of their ability to keep the seeds safe until conditions are favorable for germination, and the ease at which they can be distributed. 

In the Carolinas in the 1700’s, West African slaves, predominantly women, were brought in to cultivate rice using a seed ball technique that was used in Africa. Rice seeds were coated in clay, dried, and pressed into the mud flats with the heel of the foot. This served two purposes, protecting the seed from the birds, and also preventing it from floating off when the fields were flooded. I am surprised that this is not mentioned more in the online seed ball literature. I plant to write a more lengthy post about it soon.

A seed ball before the storm.

More recently, Japanese agricultural renegade, Masanobu Fukuoka, began exploring the use of seed balls (nendo dango in Japanese) to help improve food production in post WWII Japan. His research and outreach efforts has brought the seed ball back into the public eye.
Today, seed balls are fun for green-minded kids and adults, and are also an important tool of the guerrilla gardening movement.

A pumpkin seed ball growing in our lab.

Anatomy of Our Seed balls
Our seed balls/seed bombs are individually made in our Pennsylvania greenhouse. I like to think of them as the Ferrari of seed balls. They contain a combination of mineral soil and three types of compost. Read about the science behind our formulation on our science page. Seeds are scarified if necessary prior to placing in the seed ball. Depending on the size and requirements of the plants, seeds are either mixed in with the soil before the seed balls are made or placed individually within the moist seed ball. We carefully hand roll each seed ball until it’s just right. The seed balls are then air-dried, providing a safe haven for its contents until germination.
Our seed balls are packaged in a small recyclable brown paper bag. Nothing fancy, nothing that leaves an unnecessary footprint.

Seed Ball Anatomy

How to sow seed balls & seed bombs

Press them gently on the soil, about 2/3 of the way down. For added fun, throw them along the road, use a slingshot, or a boilie thrower.

Why our seed balls are special
We test our seeds for germination and make certain that our seed balls have excellent viability when the environment is favorable.
Our seed ball matrix is designed by Dr. Blake Ketchum and Biologist, Brian Moyer. Blake’s got a PhD in Soil Science and is nuts about soil and plants, Brian has totally got the mad experimental scientist thing going on!
We use 3 kinds of compost to super charge our seed balls for all the nutritional requirements of your plants.

Seed Balls vs Seed Bombs?

The only substantial difference is what you call them. “Bomb” sounds more subversive, and so it’s gaining popularity among guerrilla gardeners. When properly made, the seed ball or bomb will have enough seed to ensure germination, but not so many seeds that the plants will choke each other. Since the idea is to grow healthy plants, we use enough seed to ensure good likelihood of germination, but not so many that the seedlings are stressed from crowding and fail to thrive. Some folks who make seed bombs overload them with seed. They look like chia pets when they germinate, but the competing seedlings may not do so well.

Amazing Brain-Facts!

1. You have a finite amount of will power each day because to exercise will power you need energy in the form of oxygen and glucose That’s why it’s harder to say ‘no’ when you are tired or not feeling yourself.

2. A thought is a physical pathway in the brain. The more you have that thought the more you groove that path and the easier it is to have it again. That’s why having negative thoughts are never a great idea.

3. Speaking of which, you have approximately 70,000 thoughts per day, although many will be the same ones looping round and round on your grooved cranial highway.

4. Even if you consider yourself a left-brained person, your brain will still switch over to the right side every 90 to 120 minutes and then back again. That’s why even left-brained people can have times of the day when they are more creative and right-brained people can sometimes get their taxes in order.

5. Reading out loud to kids accelerates their brain development.

6. Reframing negative events in a positive light literally rewires your brain and can make you a happier person, as can regular meditation.

7. The brain is approximately 75% water, but you should never drink it.

8. Your brain only weighs about 3lbs yet uses between 20% and 25% of your energy supplies each day.

9. There are approximately 10 to the power of 60 atoms in the universe. Your brain laughs in the face of that figure however, as it has 10 to the power of 1,000,000 different ways it can wire itself up. That’s the number 10 followed up with 1 million zeroes, which is to all intents and purposes (for anybody not called Stephen Hawking or Rob Collins), an infinite amount of ways.

10. Speaking of large numbers, there are approximately 1.1 trillion cells and 100 billion neurons in the average human brain.

11. The slowest speed information passes around your brain is approximately 260 mph

12. Your brain was disproportionately large compared to other organs when you were born.

That’s why babies look a bit like aliens. Not yours of course, yours are cute, just other peoples babies.

13. If you lose blood flow to your brain you will last about 10 second before you pass out.

14. Your brain has no pain receptors which is why if I managed to remove the top of your skull without you noticing I could poke around all day without you feeling a thing. The skull removal may hurt a bit though.

15. Even though we say the amygdala regulates danger, the cerebellum motor control, and the limbic system emotions etc, this is somewhat misleading as no part operates independently and all need other parts of the brain to get their job done.

16. Your peripheral vision improves at night which is why pilots are taught to use their peripheral vision when looking for traffic.

17. Leaving aside degenerative brain disease, your brain never loses the ability to learn and change because it’s effectively plastic and constantly rewiring itself.

18. It ‘s a self development urban myth that we only use 10% of our brain. We use it all and if you don’t believe me cut a bit out and see what happens.

19. If you were to measure your brainwave activity you wouldn’t see any drop off when you’re asleep. You may be napping, but your brain is still working hard pumping your heart, digesting your food, maintaining your blood pressure and much more to make sure you don’t wake up dead.

20. Research has shown that the hippocampus which deals with visual-spatial awareness, is larger in London Taxi drivers than normal people. London ‘cabbies’ have to spend months, sometimes years, learning literally every street in the Capital before they are allowed a license. This process is known as ‘The Knowledge’ and it literally enlarges that part of their brain. Unfortunately, it doesn’t help them with anger management issues when cyclists get in their way.

21. Until relatively recently scientists thought that the brain was the only area of the human body that didn’t generate new cells. We now know that’s not true and the brain does reproduce shiny new cells for you to use

22. You have something in your brain called mirror neurons. If you see somebody stub their toe for example, the same pain area will light up in your own brain causing you to flinch.

Mirror neurons weren’t even known to exist prior to the early 1990’s, but now there is a growing belief in the scientific community they are responsible for us feeling empathy toward others.

23. When somebody takes cocaine their pleasure center (nucleus accumbens) lights up and dopamine and serotonin are released. Giving to charity or helping people in need also activates the nucleus accumbens. What a win/win that is!

24. Multi-tasking is a self development urban myth. You simply cannot do it efficiently no matter what manufacturers of smart phones want you to believe. According to the University of Utah, there are a few people (about 2.5% of the population) who can do two things consciously* at once without seeing any degradation in performance. They are called super-taskers. However, for most people all the brain is doing is going backwards and forwards very quickly and giving the illusion of multi-tasking. The reality is performance is inhibited by this approach not improved.

25. Your brain is constantly lying to you when you have your eyes open. Because it cannot deal with every single detail that you’re looking at, the occipital lobe is joining the dots with what it presumes is there.

26. Similarly, your brain doesn’t record memories like video as it would be easy to assume. It takes snapshots of the more important bits and then when you recall the event it guesses what happened in between based on prior experience.

27. Your brain finds it very easy to create false memories largely because of the above and the fact that it spends so much time guessing what’s happening.

When scientists exposed people to Photoshopped images of themselves at various event years prior they were soon able to explain what they were doing and recall the event with clarity even though they were never there.

There will be events you swear blind happened the way you remember, but never actually did. A sobering thought.

28. Your brain is fairly crap at distinguishing between what’s really happening and what you are merely imagining. Which is why horror films scare people.

29. The brain is very poor at concentrating for long periods of time and needs to clear it’s head so to speak about every 90 minutes or so. Which is why if you’re delivering training and you want to maximize results, you should allow people to take lots of mini breaks rather than one long break for lunch.

Why does a flame burn upwards?

Why does a flame burn upwards?

We are familiar with how flames burn. Let it be a tear shaped candle flame or a forest fire, it always burns upwards. We will look into the details later, but the following image released by NASA says it all - 

An illustration of how candle burns on earth and in zero gravity

Courtesy: http://science.nasa.gov/

Gravity does the magic: 

Its obvious from the above illustration that gravity has a role to play. However, one can't help but wonder why a flame would go upwards where there is strong gravitation pull like on earth and remain spherical where there is no gravity like on a space station (Is there really no gravitational pull in space?). The answer is buoyancy.

When you start a fire, fuel combines with oxygen to release heat, light, carbon dioxide, water vapor, soot etc. The heat energy generated in this process heats up the air around the flame which in turn reduces its density** (a good analogy is water vapor which is hotter and less denser as against water which is colder and heavier).

This hot air around the flame then starts rising up and the surrounding colder heavier air rushes down into its place accelerating the hot air upwards which in turn causes the flame to shoot up (a good analogy here is a wooden log dipped in water. the buoyancy pushes the log to the surface). Basically the buoyancy shoots the flame up. It is this hot air rushing upwards that also causes fire to flicker.

The following image shows what happens to the air around a flame.

Hot air around the flame rises up shoots the flame upwards

However, in a micro gravity environment, there is no reason for the heavier air to fall down and rush into the place of the lighter air. So the flame just remains a spherical blob as you would imagine. 

So there you have it. A combination and gravity and gravity induced buoyancy causes the hot air to rise up causing the flames to point upwards here on earth.

**Just in case you are curious as to why hot air is less denser than cold air in the first place - the heat gives the molecules in the gas higher (kinetic) energy. So these molecules can move faster and further apart because they now have the energy needed to overcome their binding forces. The molecules being farther apart means that the material is less dense.

The jar of life

A message given by a professor in a wonderful way.....he compared life with a empty jar

"if u spent your all energy and time for small stuff, u never get a time to manage important things"...similar like "if u fill the empty jar with sand first, u never get a place to add golf balls are anything more"

the second video can describe clearly

Total Internal Reflection (TIR) using a Soda Bottle

Figure 1: Total Internal Reflection (TIR) causes light to bend through a stream of water.

 

Figure 2: A laser is pointed at a soda pop bottle with a hole at the bottom. Total internal reflection (TIR) is produced in a stream of water due to the water and light barrier.

The Video Explanation

Explanation

When light crosses into a new medium, some of the light will refract (bend) and some of it will reflect. The angle of refraction is given by Snell's Law:

Where n is the index of refrection, a property unique to each material. This, and the reflection, is shown in the following diagram.

Figure 4: Light refracts and reflects at the barrier between air and water.

Where θ1 is the angle of incidence, or the angle of the source of light, θr is the angle of reflection, and θ2 is the angle of refraction. However, Snell's Law will result in error when n1 is greater than n2. This is called a critical angle, and it is the minimum angle at which all light is reflected. The critical angle can be defined by:

This is the limiting case. If n1 ≥ n2, then θ2 = 90°.

Figure 5: At the critical angle, light travels through the plane where the two media meet.
In this case, nair = 1.00 nwater = 1.33. Therefore:

In this demo light will continually reflect through the stream of water creating total internal reflection (TIR). The stream of water will 'carry' the light though, to the end of the stream.

Figure 6: Total Internal Reflection (TIR) causes light to bend through a stream of water.

Total Internal Reflection is the principle behind fiber optics.

Figure 7: Total Internal Reflection is used to carry light in fiber optics.

For more information see Wikipedia's entry on Fiber Optics. http://en.wikipedia.org/wiki/Optical_fiber.

   Materials

• empty soda pop bottle (2 liter)
• tape
• hand drill
• drill bits
• water
• green laser
• bucket
• old books, etc for stands

Procedure

1. First set up the soda bottle by drilling a hole near the bottom of the bottle. Begin with a drill bit that has a diameter which is slightly larger than the diameter of the laser that will be used. We used a 1/4 inch drill bit, however sizes as small as 7/32 inch worked as well. 
2. First tape the hole and then fill the bottle with water. The cap will prevent leaking because it creates a vacuum in the bottle. 
3. Stand the soda bottle on top of a stack of books so the hole is facing the bucket. The laser should be placed in a binder clip so it stays on, and then set on a stack of books and papers. The laser should be lined up so that the laser light goes through the soda bottle, and into the center of the hole. See Figure 2 (top left picture) for details. 
4. Carefully remove the tape and then unscrew the top of the soda bottle. The light should reflect within the stream of water so that you could see at least a few points of reflection. The light should be visible through the entire stream. 
5. If the reflections of the light isn't clear, it may be necessary to expand the hole by drilling through the existing hole with a larger drill bit. This process may need to be repeated several times.

    Notes

• This is an messy experiment. Be ready to adjust the bucket which catches the stream of water. 
• Also be aware that the stream's curvature will change as the water level decreases. It will bend closer to the bottle, and the bucket may need to be adjusted again. When the water level is a little above the hole there will be no total internal reflection although the stream will continue. Place the cap back on, or put the bottle inside of the bucket. 
• Make sure to have lots of paper towels! Towels or rags could be useful too. However, this mess is water, and therefore easy to clean up. 
• Some resources suggest putting a drop of food coloring in the bottom of the bucket to match the laser light, giving the appearance that the water has permanently 'trapped' the colored light. This is a magic trick, and may cause students to misunderstand what total internal reflection is.

  References

http://wildcat.phys.northwestern.edu/vpl/optics/snell.htmlThis site contains an applet which allows the user to change the angles and indices of refraction. It is a more simple and straight version compared to Stony Brook's (the link below).
http://www.eserc.stonybrook.edu/ProjectJava/snell/This site is an applet which allows the user to change the angles and indices of refraction in order to observe reflection and refraction. There is a 'simpler version' option.
http://en.wikipedia.org/wiki/Total_internal_reflection
The Wikipedia entry on Total Internal Reflection
http://hyperphysics.phy-astr.gsu.edu/Hbase/phyopt/totint.html
An explanation of total internal reflection with drawings. It includes a calculator which determines the critical angle when the indices of reflection are provided.
http://www.glenbrook.k12.il.us/gbssci/phys/CLass/refrn/u14l3b.html
This is a tutorial on Total Internal Reflection with many drawings to explain the concepts.

Using the high-low side driver IR2110 - explanation and plenty of example circuits

Using the high-low side driver IR2110 - explanation and plenty of example circuits

In many situations, we need to use MOSFETs configured as high-side switches. Many a times we need to use MOSFETs configured as high-side and low-side switches. Such as in bridge circuits. In half-bridge circuits, we have 1 high-side MOSFET and 1 low-side MOSFET. In full-bridge circuits we have 2 high-side MOSFETs and 2 low-side MOSFETs. In such situations, there is a need to use high-side drive circuitry alongside low-side drive circuitry. The most common way of driving MOSFETs in such cases is to use high-low side MOSFET drivers. Undoubtedly, the most popular such driver chip is the IR2110. And in this article/tutorial, I will talk about the IR2110.

You can download the IR2110 datasheet from the IR website. Here's the download link:

www.irf.com/product-info/datasheets/data/ir2110.pdf

First let’s take a look at the block diagram and the pin assignments and pin definitions (also called lead assignments and lead definitions):

Fig. 1 - IR2110 block diagram (click on image to enlarge)

Fig. 2 - IR2110 Pin/Lead Assignments (click on image to enlarge)

Fig. 3 - IR2110 Pin/Lead Definitions (click on image to enlarge)

Notice that the IR2110 comes in two packages – 14 pin through-hole PDIP package and the 16-pin surface mount SOIC package.

Now let's talk about the different pins.

VCC is the low-side supply and should be between 10V and 20V. VDD is the logic supply to the IR2110. It can be between +3V to +20V (with reference to VSS). The actual voltage you choose to use depends on the voltage level of your input signals. Here’s the chart:

Fig. 4 - IR2110 Logic "1" Input Threshold vs VDD (click on image to enlarge)

It is common practice to use VDD = +5V. When VDD = +5V, the logic 1 input threshold is slightly higher than 3V. Thus when VDD = +5V, the IR2110 can be used to drive loads when input “1” is higher than 3 point something volts. This means that it can be used for almost all circuits, since most circuits tend to have around 5V outputs. When you’re using microcontrollers the output voltage will be higher than 4V (when the microcontroller has VDD = +5V, which is quite common). When you’re using SG3525 or TL494 or other PWM controller, you are probably going to have them powered off greater than 10V, meaning the outputs will be higher than 8V when high. So, the IR2110 can be easily used.

You may lower the VDD down to about 4V if you’re using a microcontroller or any chip that gives output of 3.3V (eg dsPIC33). While designing circuits with the IR2110, I had noticed that sometimes the circuit didn’t work properly when IR2110 VDD was selected as less than +4V. So, I do not recommend using VDD less than +4V.

In most of my circuits, I do not have signal levels which have voltages less than 4V as high and so I use VDD = +5V.

If for some reason, you have signals levels with logic “1” having lower than 3V, you will need a level converter / translator that will boost the voltage to acceptable limits. In such situations, I recommend boosting up to 4V or 5V and using IR2110 VDD = +5V.

Now let’s talk about VSS and COM. VSS is the logic supply ground. COM is “low side return” – basically, low side drive ground connection. It seems that they are independent and you might think you could perhaps isolate the drive outputs and drive signals. However, you’d be wrong. While they are not internally connected, IR2110 is a non-isolated driver, meaning that VSS and COM should both be connected to ground.

HIN and LIN are the logic inputs. A high signal to HIN means that you want to drive the high-side MOSFET, meaning a high output is provided on HO. A low signal to HIN means that you want to turn off the high-side MOSFET, meaning a low output is provided on HO. The output to HO – high or low – is not with respect to ground, but with respect to VS. We will soon see how a bootstrap circuitry (diode + capacitor) – utilizing VCC, VB and VS – is used to provide the floating supply to drive the MOSFET. VS is the high side floating supply return. When high, the level on HO is equal to the level on VB, with respect to VS. When low, the level on HO is equal to VS, with respect to VS, effectively zero.

A high signal to LIN means that you want to drive the low-side MOSFET, meaning a high output is provided on LO. A low signal to LIN means that you want to turn off the low-side MOSFET, meaning a low output is provided on LO. The output on LO is with respect to ground. When high, the level on LO is equal to the level of VCC, with respect to VSS, effectively ground. When low, the level on LO is equal to the level on VSS, with respect to VSS, effectively zero.

SD is used as shutdown control. When this pin is low, IR2110 is enabled – shutdown function is disabled. When this pin is high, the outputs are turned off, disabling the IR2110 drive.

Now let’s take a look at the common IR2110 configuration for driving MOSFETs in both high and low side configurations – a half bridge stage.

Fig. 5 - Basic IR2110 circuit for driving half-bridge (click on image to enlarge)

D1, C1 and C2 along with the IR2110 form the bootstrap circuitry. When LIN = 1 and Q2 is on, C1 and C2 get charged to the level on VB, which is one diode drop below +VCC. When LIN = 0 and HIN = 1, this charge on the C1 and C2 is used to add the extra voltage – VB in this case – above the source level of Q1 to drive the Q1 in high-side configuration. A large enough capacitance must be chosen for C1 so that it can supply the charge required to keep Q1 on for all the time. C1 must also not be too large that charging is too slow and the voltage level does not rise sufficiently to keep the MOSFET on. The higher the on time, the higher the required capacitance. Thus, the lower the frequency, the higher the required capacitance for C1. The higher the duty cycle, the higher the required capacitance for C1. Yes, there are formulae available for calculating the capacitance. However, there are many parameters involved, some of which we may not know – for example, the capacitor leakage current. So, I just estimate the required capacitance. For low frequencies such as 50Hz, I use between 47µF and 68µF capacitance. For high frequencies like 30kHz to 50kHz, I use between 4.7µF and 22µF. Since we’re using an electrolytic capacitor, a ceramic capacitor should be used in parallel with this capacitor. The ceramic capacitor is not required if the bootstrap capacitor is tantalum.

D2 and D3 discharge the gate capacitances of the MOSFET quickly, bypassing the gate resistors, reducing the turn off time. R1 and R2 are the gate current-limiting resistors.

+MOSV can be up to a maximum of 500V.

+VCC should be from a clean supply. You should use filter capacitors and decoupling capacitors from +VCC to ground for filtering.

Now let’s look at a few example application circuits of the IR2110.

Fig. 6 - IR2110 circuit for high-voltage half-bridge drive (click on image to enlarge)

Fig. 7 - IR2110 circuit for high-voltage full-bridge drive with independent switch control (click on image to enlarge)

In Fig. 7 we see the IR2110 being used to drive a full bridge. The functionality is simple and you should understand it by now. A common thing that is often done is that, HIN1 is tied/shorted to LIN2 and HIN2 is tied/shorted to LIN1, enabling the control of all 4 MOSFETs from 2 signal inputs, instead of 4 as shown below in Fig. 8.

Fig. 8 - IR2110 circuit for high-voltage full-bridge drive with tied switch control - control with 2 input signals (click on image to enlarge)

Fig. 9 - Using the IR2110 as a single high-voltage high-side driver (click on image to enlarge)

In Fig. 9 we see the IR2110 being used as a single high-side driver. The circuit is simple enough and follows the same functionality described above. One thing to remember is that, since there is no low-side switch, there must a load connected from OUT to ground. Otherwise the bootstrap capacitors can not charge.

Fig. 10 - Using the IR2110 as a single low-side driver (click on image to enlarge)

Fig. 11 - Using the IR2110 as a dual low-side driver (click on image to enlarge)

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If you've had failures with IR2110 and had driver after driver, MOSFET after MOSFET get damaged, burn and fail, I'm pretty sure that it's due to you not using gate-to-source resistors, assuming of course that you designed the IR2110 driver stage properly. NEVER OMIT THE GATE-TO-SOURCE RESISTORS. If you're curious, you can read about my experience with them here (I have also explained the reason that the resistors prevent damage):

http://tahmidmc.blogspot.com/2012/10/magic-of-knowledge.html