Introduction

Nice to meet you.
I am a Kansai native from Hyogo prefecture.

I will continue to post "analog" related articles.
Thank you for your support for 1 years! !

Power supply definition

Any source of power supply can be called a power supply.
Switches, outlets, batteries, etc. are all power sources.

Power supply role

The role of a power supply is to provide power to anything that is powered by electricity.
Here, we will use dry batteries as an example to explain how a power supply supplies power.


Consider the case of using batteries in a TV remote control. Dry batteries generally have a nominal voltage of DC (direct current) 1.5V.
Since the remote control uses two batteries, 1.5 x 2 = 3V will be supplied.

Put in batteries and the remote will work. However, if the dry battery continues to be used, the voltage that can be supplied will drop steadily from 3V.

Then, can a dry battery function as a power supply when the voltage drops compared to when it was new? ?

《Commentary》
When we change channels on our TV, we point the remote control at the TV and press a button.
At this time, an electrical signal is sent from the remote control to the TV.
This electrical signal originates from the signal processing electronic board built into the remote control (Fig. 1).

Also, when we want to change the TV channel, we can do so with the push of a button.
At this time, the inside of the remote control detects the action of pressing the button and controls to send an electrical signal to change the channel to the TV.
A device called a microcomputer is responsible for this control, and is mounted on an electronic board.

Let's take a look at the image from when we press the remote control button until the electrical signal is sent (Figure 2).

As shown in Figure 2, power is also required to run the microcomputer. The power supply for the remote control is 3V, which is equivalent to two dry batteries.
However, depending on the type of microcomputer, a voltage of 3V or more may be required for operation.
As an example, consider a microcomputer that requires 3.3V to operate.

In addition, since the battery voltage drops steadily from 3V, it is not possible to supply 3.3V to the microcomputer.
In this state, the microcomputer cannot operate, and no electrical signal is transmitted from the electronic board.

In such cases, power supply ICs appear.
A simple representation of the role of the power supply IC is shown (Fig. 3).

A ⇒ The microcomputer does not work because the battery voltage is insufficient.
B ⇒ The microcomputer operates because the power supply IC creates the operating voltage for the microcomputer

As shown in Figure 3, an IC called a power supply IC is mounted in the electronic board, and it creates and supplies the appropriate voltage for the microcomputer to operate.
This allows the remote control to continue working even if the voltage supplied by the batteries drops below 3V.
In the example above, a voltage of 2-3V is converted to 3.3V.
In other words, the power supply IC plays the role of increasing the voltage.

Power supply IC type

Power supply ICs are classified into several types according to the conversion method.

at the end

This time, I explained the introductory version about "power supply".
Next time, I will explain DC-DC converters, which have the largest variety of power supply ICs.
Finally, we would like to introduce the analog IC manufacturers that we deal with.

Analog Devices

A leading manufacturer of high-performance standard analog ICs.
We determine the performance and quality of our customers' final products, such as amplifiers, battery management, data converters, high frequencies, interfaces, voltage regulators, and voltage references, and achieve stable supply.
In principle, we will not discontinue the production of our products, so customers who use our products for a long period of time, such as industrial equipment, can use them with peace of mind.