{"id":1477,"date":"2021-07-06T19:01:35","date_gmt":"2021-07-06T19:01:35","guid":{"rendered":"https:\/\/www.axcontrol.com\/blog\/?p=1477"},"modified":"2023-09-25T16:39:38","modified_gmt":"2023-09-25T16:39:38","slug":"how-to-identify-components-on-printed-circuit-boards","status":"publish","type":"post","link":"https:\/\/www.axcontrol.com\/blog\/2021\/how-to-identify-components-on-printed-circuit-boards\/06\/07\/","title":{"rendered":"How To Identify Components on Printed Circuit Boards"},"content":{"rendered":"\n
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It can be hard to identify all the components on printed circuit boards (PCBs). <\/figcaption><\/figure>\n\n\n\n

If you’ve ever tried to work on your own PCBs, or printed circuit boards, you may have experienced the frustration of looking at a part and not knowing exactly what it is. After working with thousands of PCBs, we understand. <\/p>\n\n\n\n

Luckily, there are resources that can help. In fact, lots of them. But they’re scattered all over. And many of the best aren’t even available online anymore unless you know how to use some special tools (Wayback Machine to the rescue!) <\/p>\n\n\n\n

But rather than complain about this state of affairs, we decided to create our own tutorial to fix it. Bonus: you benefit, too. <\/p>\n\n\n\n

Here’s our printed circuit board component tutorial, with lots of information and pictures to help you identify those individual parts. <\/p>\n\n\n\n

Printed Circuit Boards: the Basics<\/h2>\n\n\n\n

Printed circuit boards are typically made from laminated composite material. This non-conductive substrate sandwiches copper circuitry that actually makes up the circuits the boards are named after. <\/p>\n\n\n\n

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substrate: \/\u02c8s\u0259b\u02ccstr\u0101t\/; an underlying substance or layer.<\/p>\nmudcoders.com<\/cite><\/blockquote>\n\n\n\n

These copper circuits, also known as signal traces, electrically connect and mechanically support other mounted components on the board. <\/p>\n\n\n\n\n\n\n\n

Why are PCBs green?<\/strong> That’s actually the solder mask showing up through the fibreglass core of the board. Solder protects the copper circuits and prevents short circuits. The green solder casts a tint on the glass pieces protecting it. <\/p>\n\n\n\n

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solder mask: \/\u02c8s\u00e4d\u0259r mask\/; a protective layer of liquid photo imagable lacquer that has been applied to the top and bottom of PCBs to protect copper from oxidation and dust. <\/p>\neurocircuits.com<\/cite><\/blockquote>\n\n\n\n

How To Identify Components Step-by-Step<\/h2>\n\n\n\n

Like most things in life, identifying components becomes easier when you break the task down into smaller parts. <\/p>\n\n\n\n

Identify Board Use<\/h3>\n\n\n\n

First, try to identify the entire board. What is it used for? Is it a motherboard, a daughterboard, or does it perform a particular task? Some boards are marked with codes that will help with this process. For example, the DMCB board pictured below is a D<\/strong>OS M<\/strong>ain C<\/strong>ontrol B<\/strong>oard for a GE Mark V system. Many GE board acronyms are like this. They can help you figure out the board application.<\/p>\n\n\n\n

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Motherboard: a PCB with principal components and connectors for other PCBs to be mounted. Daughterboard: an expansion PCB that attaches to a motherboard to access the CPU and memory. <\/p>\nAX Control<\/cite><\/blockquote>\n\n\n\n

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This GE DS200DMCBG1ABB PCB<\/a> functions as a D<\/strong>OS M<\/strong>ain C<\/strong>ontrol B<\/strong>oard, or DMCB.<\/figcaption><\/figure>\n\n\n\n

Identify the Parts<\/h3>\n\n\n\n

Next, identify passive components like capacitors and inductors. Don’t worry, we’ll have pictures later in this post. Then look for resistors and potentiometers. These will usually have an ohm measurement mark. The symbol for an ohm is the Greek letter Omega, which looks like this: \u03a9<\/strong>. 100M\u03a9 translates to 100 megaohms.<\/p>\n\n\n\n

Other easy-to-identify components include oscillators (cylinders or boxes typically marked with X or Y), transformers (T), diodes (D), and relays (marked as K). <\/p>\n\n\n\n

Now look to see if the board has a fuse. Fuses are often clear or opaque tubes. Then try to identify any batteries or transistors. <\/p>\n\n\n\n

Identify any board connectors. Connectors are used to attach other circuit boards or to attach the board to a larger system or outside components. <\/p>\n\n\n\n

There are so many different kinds of connectors you could spend months learning them all, but the most common are backplanes, terminal blocks, pin headers and the sockets that accept them, and jacks or plugs. <\/p>\n\n\n\n

Finally, identify the processor and other integrated circuits on the board. Many ICs will have their manufacturer and part number label or ID. If so, you may be able to look up an individual datasheet to learn more about the chip. <\/p>\n\n\n\n

Printed Circuit Boards: Most Common Components <\/h2>\n\n\n\n

While PCBs can have many different mounted components, eight make up the most common. These include<\/p>\n\n\n\n

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This circuit board offers a view of common PCB parts including capacitors, resistors, transistors, and diodes. Right-click to open for a full-size image to see marks on the PCB surface.<\/figcaption><\/figure>\n\n\n\n