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Why the Voltage Divider Formula is Important

Voltage divider formula is a complete yet user-friendly tool that enables you to assess the output signals (i.e. voltage) which is produced by one voltage divider, which is frequently used for voltage regulators.

Continue reading to find out what the voltage divider formula is, its basic calculator, and the way it applies to different equations for various types of voltage divider. Learn how this voltage divider formula and rule can be used to obtain a portion of the input voltage.

Consider the myriad ways the voltage divider is used in both simple and extremely complicated systems to further persuade yourself that the electronic circuits shouldn’t be anything to get concerned about.

What Does a Voltage Divider Mean?

The voltage divider can be described as a straightforward circuit that lowers voltage. It equally distributes its input voltage amongst some of the circuit’s components. Two resistors linked in series, and with input voltages applied across its resistor pair as well as the output voltages drawn from the point in between, are the best representation of the voltage divider.

It’s employed to generate various levels of voltage from a single source of voltage while maintaining a constant current for each component in series circuits.

Voltage Divider Formula and Calculator

Inductor voltage and current waveforms
Inductor voltage and current waveforms

The output voltages of the voltage divider always reduce its input voltage as well as the current that flows through a series network, which is determined by Ohm’s Law, (V=IR). The current between them is equal since this current is shared by both resistors. We can figure out the voltage that was lowered across the second resistor, with the help of this formula.

The voltage passing across many resistors connected in series having a DC source of voltage can be calculated using the voltage divider formula and calculator (can handle about 10 resistors).

Calculating the entire resistance of the whole circuit in series is how the voltage divider operates. Voltage divider formula is then applied, with Resistor 1 serving as the particular resistor which we are attempting to calculate the drop in voltage across is. For each resistor in voltage divider circuits, this calculation is repeated.

The higher the resistance values of the elements, the more voltage would be lost across them, according to Ohm’s law. Likewise, less voltage passes through resistors having lower values for resistance.

The VIN, input voltage, as well as resistor values, ranging between 1 and 10, must both be entered in order to utilize the voltage divider formula and calculator (to serve multiple resistors connected in series). Then, the user must click on “Calculate” button. Each resistor entered will have its voltage drop calculated and then automatically displayed. This voltage’s outcome is calculated in volts.

The voltage divider formula for a voltage divider circuit of two resistors is Vout=Vin(R2R1+R2), while for two resistors, it is VRx=Vin(Rx/RT).

What is the Rule for the Voltage Divider?

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The idea behind the voltage dividers indicates that though this voltage is divided in some way across the series-connected parts, the current flowing through them remains constant. To determine the precise numbers for our circuit, you must use Ohm’s law. To start, we must make the following very important information:

The only composition that applies to DC circuits is RR composition. In these circumstances, any impedance can be regarded as wires having zero resistance, and capacitances function as a circuit’s gap, where they have an infinite resistance. The rule for voltage divider is valid for the highest value of potential difference for the remaining ones, which are all employed with AC circuits. Finding a phase shift to suit these voltages might be just as useful.

Voltage Ladder

The circuit known as the voltage ladder consists of many resistors connected in series having a voltage applied across the whole network of resistors. The voltage drop of every resistor in these networks is greater than that of the one preceding it.

The current remains constant across the entire ladder because the resistors are connected in series. Divide the entire voltage by total resistance to obtain its value. By multiplying the entire current by each resistor’s value, one may determine each resistor’s voltage drop. The total of voltages lost by every resistor between a node as well as ground can be used to define the voltage referred to ground at every given node.

Input Voltage and Voltage Drop

The output voltages and divided voltage throughout the circuit are both determined by the drop in voltage across R2. Two resistors are connected in series to provide a voltage divider that is referenced to the ground.

R1 as well as R2 are connected in series to form an input voltage, while R2 receives its output voltage. There is therefore nowhere else for the same amount of current which passes through every resistive component of circuits. Therefore, this delivers a voltage drop of IxR across every resistive element as a result.

We can use the voltage law of Kirchoff and Ohm’s Law in determining the drop in voltage across every resistor based on the current flowing across them after knowing the supply voltage.

What are the Applications of the Voltage Dividers?

Below are some of the uses for voltage dividers:

A potentiometer is a well-known device that utilizes the concept of the voltage divider. This component is also known as a rheostat.

Typically, they are made entirely of resistive parts. We can differentiate between digital as well as analog ones, but we can tune the resistance using extreme precision in either case. Slide pots, trim pots, and thumb pots are some most well-liked varieties of potentiometers, and they differ in size and construction. The sliding contact, which makes it possible to alter the resistance of the output, is the key component.

Equipment for measuring high voltage – This comes out that high voltages can be measured, despite the fact that direct measurements may be harmful to the instrument. In that situation, it is practical to drop the voltage onto a secure area using a voltage divider. It is preferable to utilize capacitive devices rather than resistive ones at really high voltages.

Locating an unidentified resistance:  If you just have the voltage source as well as another resistor having a known resistance, is it still possible to detect any unknown resistance? If you’re able to understand the color code, you’re lucky, yet what happens when there isn’t?

You can, however, just build a straightforward circuit with two resistors connected in series, choose input voltage, but then gauge the voltage across the required resistance. The enigma is then solved by simply entering all of these values in to voltage divider formula and calculator. The general equation for voltage divider can always be transformed to determine.

What are the Benefits and Drawbacks of the Voltage Dividers?

Several of you might be questioning why someone would use a voltage divider for measuring an unknown resistance whenever they could merely read the amount of amperage which passes via the resistor whenever any external voltage has been applied—a straightforward application of Ohm’s law. So, generally speaking, there shouldn’t be much of a difference between both approaches, but we have to be conscious that most materials’ resistance is dependent on temperature. Even worse, the dependencies for insulators, semiconductors, and metals are different.

As metals’ resistance rises as the temperature does, we must determine the thermal coefficient of the material in order to quantify the resistance at a standard temperature. This calls for carefully measuring the surrounding temperature, performing some calculations, and hope that there were no mistakes during the meantime.

But we can make it much easier than that! You might employ a straightforward voltage divider, as you would have thought!

More Benefits and Drawbacks

Two resistors are present in the basic form, and as they are constructed out of a single material, the temperature dependence on resistance are essentially the same. These resistances vary at roughly the same rate, regardless of the size of the temperature differential. Although any change will balance out because this voltage divider formula often has the ratio of different impedances, the voltage of the output should be independent of temperature. Also, if we examine the formula from the preceding section, we’ll get a resistance value that is just like the initial one at any specific temperature.

Second, while designing some intricate electrical circuits, it’s indeed practical to utilize voltage dividers. We may employ one source as well as voltage dividers needed, as opposed to employing several independent voltage sources that each produce a unique potential inside the system.

On the contrary, we must be mindful that the drop in voltage is more likely the longer its circuit’s wires are. Although the likelihood is far lower than it would be for the long industrial cable, the issue should still be considered and ideally avoided wherever possible if we have to perform some precise measurements.

Conclusion

What we’ve previously accomplished demonstrates how the voltage dividers function for the most basic systems. Second, it’s practical to utilize voltage dividers while creating some.  One can probably guess they are utilized nowhere in reality and that more advanced circuits are typically employed.

Yet, all of the aforementioned findings may be useful in order to simplify more complicated ones. For example, you may treat a group of resistors as one single resistance if you are able to see them arranged in a series or parallel.