Linear Regulator vs Switching Regulator: Key Difference Explained

Linear Regulator vs Switching Regulator: Key Difference Explained

Creating and maintaining a fixed output voltage is an essential function. Voltage regulators are the electronic devices that help with this. The linear and switching regulators are the most commonly used voltage regulators. You might get confused between these two. However, differentiation between them is crucial to understanding their working and applications. This is why we have developed this guide on linear regulator vs switching regulator. So, start reading below to learn all the differences between these two types of voltage regulators. 

What is a Linear Regulator?

A linear voltage regulator is a device used to maintain a specific output voltage despite the variations in input voltage and load conditions. These regulators use an active pass device controlled by a high-gain amplifier. The variable conductivity of this active pass element maintains the output voltage. A linear voltage regulator functions as a voltage divider to generate regulated output voltage. These regulators are of the following two types- 

  • Series Regulators
  • Shunt Regulators

How Does a Linear Voltage Regulator Work?

The primary function of a linear voltage regulator is to maintain the specified voltage output. These regulators operate using a series pass transistor controlled by a feedback loop. Linear voltage regulators have three primary components- a reference voltage source, a pass transistor and an error amplifier. 

The transistor receives the input voltage. An error amplifier samples and compares the output voltage to the reference voltage. If the output voltage deviates from the reference value, the amplifier adjusts the gate or base of the transistor to vary its resistance to maintain a steady output. 

Linear Voltage Regulator Applications

After comprehending how a linear voltage regulator works, it's now time to take a look at the various applications of a linear voltage regulator. 

  • The most common application of these regulators is the mobile chargers. The adapters that you use regularly are supplied with AC signals. These adapters regulate the AC into a regulated DC signal. 
  • Every power supply in this world uses voltage regulators to provide the desired voltage. All sorts of devices like laptops, computers and televisions are powered using this concept. 
  • The power generation systems also make use of linear voltage regulators. For example, these regulators regulate the output signals from solar power plants. 

What is a Switching Regulator?

A switching regulator is another type of voltage regulator. It is a DC-DC converter that stabilises the power supply. These regulators convert input direct current into the desired direct current voltage. Electronic and other devices use these regulators to convert the voltage from a battery or other power sources to voltages required by subsequent systems. Switching voltage regulators are of the following two types- 

  • Isolated Regulators
  • Non-Isolated Regulators

How Does a Switching Voltage Regulator Work?

A switching voltage regulator efficiently converts one DC voltage level to another DC voltage level by using a high-frequency switching element. These regulators operate by rapidly turning the switch on and off. This creates a pulsating voltage, which is then smoothed to a stable output by a capacitor and an inductor. 

The current flows through the inductor when the switch is on in a switching regulator. This stores energy in its magnetic field. The inductor releases this energy when the switch is off to maintain current flow to the load. The ratio of on-time to off-time is known as the duty cycle of the regulator that controls the output voltage. A feedback loop that typically consists of a comparator or an error amplifier adjusts the duty cycle to maintain output voltage stability regardless of the changes in input voltage or load conditions. 

Switching Voltage Regulator Applications

Switching voltage regulators have a wide range of applications, as follows. 

  • These regulators are used in consumer electronic devices like smartphones, televisions and laptops to maintain power efficiency. 
  • Switching voltage regulators are used in the automotive industry in LED headlights, electronic control units and infotainment systems. 
  • These regulators also have industrial applications as they are used in automation, renewable energy, and power tools. 

Difference Between Switching Regulator and Linear Regulator

Differentiating Factor

Linear Regulator

Switching Regulators

Design Flexibility

Buck

Buck, Boost, Buck-Boost

Efficiency

Low to medium-high for low difference between VIN-VOUT

High

Complexity

Low

Medium to high

Size

Small to Medium, greater at high power

Smaller at similar higher power

Total Cost

Low

Medium to high

Ripple/ Noise/ EMI

Low

Medium to high

Read More:-  ALL YOU NEED TO KNOW ABOUT AUTOMATIC VOLTAGE REGULATORS

To Sum Up

In conclusion, linear and switching voltage regulators are crucial in managing power supply in various electronic applications. Linear regulators are simpler, provide clean output, and are ideal for low-noise requirements but inefficient for high-voltage drops. While more complex, switching regulators offer greater efficiency and flexibility in a wide range of applications, especially where power conservation is critical. Understanding a detailed linear vs switching regulator comparison helps select the appropriate regulator for your needs, balancing efficiency, complexity, cost, and performance.

For high-quality linear and switching regulators, visit the Schneider eShop, where you can find various products to meet your power management needs.

Frequently Asked Questions

Q1. Which Regulator is More Suitable for Battery-Operated Devices?

Ans: Switching regulators are more suitable for battery-operated devices. This is because of their high efficiency that extends their battery life by minimising power loss. 

Q2. When Should I Use a Linear Regulator Over a Switching Regulator?

Ans: You must use a linear regulator when low cost, simplicity, low noise and good transient response are a priority and efficiency is less critical. These regulators are easy to design and use, making them suitable for simple power supply needs. 

Q3: What are Linear Regulators Preferred for Low-Noise Applications?

Ans: For low-noise applications, linear regulators are preferred because they operate without high-frequency switching. This results in minimal electromagnetic interference and noise.