Linear vs. Switching Regulators

Learn how to decide if a low powered linear regulator or highly efficient switching regulator is a better option for your design.

Linear Regulators

Linear regulators are a great choice for powering very low powered devices or applications where the difference between the input and output is small. Even though they are easy to use, simple and cheap, a linear regulator is normally inefficient. The equation for dissipated power in a linear regulator is:

Power dissipation = (input voltage – output voltage) × load current

Switching Regulators

Switching regulators on the other hand are highly efficient and available as modular chips which are compact and reliable. Switching regulators can be further divided into isolated and non-isolated.

  Linear Regulator Switching Regulator
Control
Design Flexibility Buck Buck, Boost, Buck-Boost
Efficiency Normally low to medium-high for low difference between VIN-VOUT High
Complexity Low Medium to high
Size Small to medium, larger at high power Smaller at similar higher power (depending on the switching frequency)
Total Cost Low Medium to high – external components
Ripple/Noise/EMI Low Medium to high
VIN Range Narrow (depending on power dissipation) Wide

Power Savings Between LDO and Switching Regulators

Positives: Simple, low cost

Negatives: Power dissipation

Efficiency Curve for LDO and Switching Regulators

Positives: Efficient, high power

Negatives: Noisy, complicated

Linear Regulators

Intersil's standard and lowdropout (LDO) regulators provide a variety of simple, low cost and low noise solutions.

View linear regulator products »

Switching Regulators

Intersil offers a wide range of step-down (buck), buck-boost, step-up (boost) switching regulators that operate with both synchronous and non-synchronous internal switches (FETs).

View switching regulator products »

For More Information

Industrial Power Solutions Industrial Power Solutions

lc-115.pdf (1.81 MB)
May 2016