Forward - I've learned a lot. Have you ever seen the cross-section of a BGA packaged chip?

btty038

Forward - I've learned a lot. Have you ever seen the cross-section of a BGA packaged chip? [Copy link]

1. DIP switch

This is a cross section of a plain old DIP switch. There are four groups of switches in this component. This is one of the switches.

This is the annotated version. It looks very simple. The slider has two sliding heads. It is a symmetrical plastic part that can be installed in any direction. Only one of them is used now. Haha, this is what the inside of the switch looks like.

2. Slide switch

Cross section of a slide switch, SPDT, which is quite cheap.

Annotated version. When you flip the switch, the joystick forces the ball to press against the shrapnel, exerting pressure on the other side. It feels a bit like a seesaw.

3. Reed relay

This is a cross section of a miniature reed relay. These are used by the tens of thousands in semiconductor test equipment and then discarded after a million cycles, but in fact, this number is much less than you think!

This is the annotated version. When this counter exceeds

At 1,000,000, the relay should be unplugged and discarded!

4. DE-9 plugs and sockets

Have you ever wondered what the inside of a D-sub connector looks like? This is a cross section of a DE-9 plug and socket. Take a closer look. Do you see any subtle features?

5. Plugs and sockets

Ever wonder what a 0.1-inch plug and socket look like when plugged together? Don’t get the wrong idea. Take a closer look at this cross section.

6. Electret microphone

Cross section of an electret microphone

Annotated version

You can see here the electret film coating on the backing plate, the metallized film was torn and deformed during the slicing process.

How it works: The metallized diaphragm and back plate act as the two plates of a parallel plate capacitor. The electret material sits in between, along with a small air gap. The electret gives this capacitor a constant charge, Q... and since C = e0 * A / d, the capacitance changes as the diaphragm deflects due to sound entering, and since Q = CV, the voltage V = (Q / Ae0) * d. In other words, the voltage is proportional to the change in distance between the two plates.

7. Digital tube

Look at this cross section of a 7-segment LED display. We can see the tiny LED chips.

Annotated version

In fact, the LED part is still on.

8. Optocoupler

Have you ever wondered what is inside an optocoupler? Wonder no more, look at the picture below

9. Headphone jack

Headphone plug and jack, cross section of a 3.5mm headphone plug. Here you can see all the switches in the jack, one of which is for disconnecting the built-in speaker. Can you find it?

Cross section of an annotated version of the headphone plug and jack

10. BGA

Cross section of BGA chip package!

Annotated version

Detail showing vias in the lower substrate

That’s all for this sharing. I’ll share more with you next time if there’s any update!

ddlxiaoxu

Weird! The optocouplers I saw when I was a kid were different from this one, so I smashed three of them and they were all the same. Both of them had a small package inside and a large one outside.

When I was a kid, I saw a TV power supply that was struck by lightning. The optocoupler was blown apart, leaving only half, and there was a red transparent piece separating it, and it was placed diagonally.

btty038

ddlxiaoxu posted on 2019-9-20 14:06 Strange! The optocouplers I saw when I was a kid were different from this one, so I smashed three of them, and they were all the same. Both of them have a small package inside and a big one outside. ...

All the people who were smashed to death are still dead.

led2015

It is indeed powerful. Many things, when disassembled, will be far beyond your imagination and difficult to understand.

btty038

led2015 Published on 2019-9-21 00:00 It is indeed very powerful. Many things, when disassembled, will far exceed one's imagination and are difficult to understand

This is another world, box, box

蒋星雨

I really didn't pay attention to these details.