What are efficiency and standby power consumption?

AC/DC Power Adapter, we provide an easy-to-understand explanation of efficiency in switching power supplies and what standby power consumption is.

AC/DC Power Adapter: What Are Efficiency and Standby Power Consumption in Switching Power Supplies?

Efficiency: EFFICIENCY

Efficiency is defined by input active power and output power, and is expressed by the formula below.

The amount of energy supplied from the outlet = input active power,
compared to the amount of energy supplied (output) from the AC/DC Power Adapter = output power.

For example, when exchanging a 1,000 yen bill, the total amount remains 1,000 yen if you receive ten 100 yen coins. However, if a 100 yen exchange fee is charged and you receive only nine 100 yen coins (900 yen), the efficiency can be expressed as 900 yen (output) ÷ 1,000 yen (input) x 100 = Efficiency: 90%.

If the efficiency were 100%, it would be an ideal AC/DC Power Adapter. In reality, however, energy used internally and conversion losses occur, making it impossible to achieve 100% efficiency.

The above specification indicates compliance with Level V of the efficiency standards established by the CEC (California Energy Commission).

From the currency exchange example, the efficiency may seem quite poor. However, with transformer-type AC/DC Power Adapter, which were mainstream nearly 20 years ago, efficiencies of around 50% were common.
With the shift to the now-mainstream switching adapters, efficiency has improved dramatically, and today most Products achieve efficiencies exceeding 80%.

What Is Standby Power Consumption?

Standby power consumption defines the power consumed during standby mode.
It refers to the power consumed when the AC/DC Power Adapter is connected to an outlet but not connected to any output.

For example, this can be compared to small water droplets leaking even when a faucet is tightly closed.
While a properly functioning faucet does not leak, in the case of an AC/DC Power Adapter, it is technically difficult to reduce standby power consumption to zero. If it is absolutely necessary to eliminate standby power consumption, measures equivalent to shutting off the main water valve are required, such as "unplugging the AC/DC Power Adapter from the outlet" or "using a power strip with a switch and turning it off."

The above specification indicates that standby power consumption is 0.3W or less.

For high-efficiency AC/DC Power Adapter and switching power supplies, leave it to our company with extensive experience.

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