Enter the linear regulator input (watts) and the linear regulator output (watts) into the calculator to determine the Linear Regulator Efficiency. 

Linear Regulator Efficiency Formula

The following formula is used to calculate the Linear Regulator Efficiency. 

Elr = RO/ RI *100
  • Where Elr is the Linear Regulator Efficiency (%)
  • RI is the linear regulator input (watts) 
  • RO is the linear regulator output (watts) 

To calculate the linear regulator efficiency, divide the regulator output by the regulator input, then multiply by 100.

How to Calculate Linear Regulator Efficiency?

The following two example problems outline how to calculate the Linear Regulator Efficiency.

Example Problem #1:

  1. First, determine the linear regulator input (watts). In this example, the linear regulator input (watts) is given as 30.
  2. Next, determine the linear regulator output (watts). For this problem, the linear regulator output (watts) is given as 25.
  3. Finally, calculate the Linear Regulator Efficiency using the equation above: 

Elr = RO/ RI *100

Inserting the values from above and solving the equation: 

Elr = 25/ 30 *100 = 83.334 (%)


Example Problem #2: 

Using the same process as above, first define the variables required by the formula. In this case, these values are:

linear regulator input (watts) = 600

linear regulator output (watts) = 100

Entering these values yields:

Elr = RO/ RI *100 = 16.66 (%)