Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [integrated-circuit]

An integrated circuit (IC) is an electronic circuit built onto a single plate of a semiconductor material, normally silicon. Modern ICs may contain billions of transistors and they have played a major part in the miniaturization and performance improvements of modern electronic systems.

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What kind of components are black blobs on a PCB?

In low-cost mass-produced items I often run into black blobs of what looks like resin applied directly on top of something on the PCB. What are these things exactly? I suspect this is some kind of custom IC that is layed out directly on the PCB to…
drxzcl
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Why is my circuit so incredibly sensitive to electric fluctuation?

I recently finished building a circuit showcased in a beginner’s electronics book. I have included the picture of my creation below because I think it may become relevant to the question. At the beginning of the build process, the instructions…
T555
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How are integrated circuits fabricated?

How are integrated circuits (e.g. a microprocessor) fabricated from start to finish? For example, there must be some wiring with resistors, capacitors to store energy (bits) in a field, transistors, etc.... How is this done? What machinery and…
Holly Jona
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Can I cut an IC?

As far as I understand, the die of a DIP package is located at the center and the rest is just the lead frame. Given that I have unused pins, can I cut the top part of this microcontroller (ATmega16/32)? Will it still function afterwards? Edit:…
v.m.
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What does 3V3 or 1V8 mean?

While reading a datasheet for an IC I came across the pin voltages being presented as 3V3 or 1V8. What does this representation stand for?
Ankit
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What are these "dogbone" traces for on (1970s era) PCB?

I've been spending some time with some old PCBs from the 70s. I have seen this pattern on some, which are these short traces that appear as little whiskers in between each of the IC lead/leg through-holes. (This pic is obviously unpopulated.) They…
BZo
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Why do ICs have NC (No Connection or No Function) pins?

In case they have no use to the end users and have no function, why are they given as pins instead of being just closed? Some ICs have even 4-5 NC continuously (in accordance to their pin number).
Ajith Natarajan
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What is a "DIE" package?

In a list of ICs, along with the familiar package names such as QFN32, LQFP48, etc., I've seen a few ICs to be listed as DIE for the package size. I've never seen that description before as an IC package size, and Wikipedia does not list it…
vsz
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Why do microcontrollers have so little RAM?

Maybe this is more of a perceptional problem, but it seems like microcontrollers have advanced by leaps and bounds in the last 20 years, in almost all regards, higher clock speed, more peripherals, easier debugging, 32-bit cores, etc... It is still…
Grady Player
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Parts shortage, no stock, what now? (canonical reference question)

As a small business, student, or hobbyist, sometimes the parts I need are unavailable (no stock anywhere). Maybe authorized distributor will take order but they will not ship for 10, 20, 30 weeks, which is a very long time to wait. If I search on…
MarkU
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Reason of multiple GND and VCC on an IC

What is the reason that most of ICs (e.g. MCU) has multiple (A/D)GND and (A)VCC pins? If it is to increase performance of an IC, how does it help to performance? or is it easier for the IC designer to connect some pins externally? some footprint…
Angs
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Why do we need so many transistors?

Transistors serve multiple purposes in an electrical circuit, i.e switches, to amplify electronic signals, allowing you to control current etc... However, I recently read about Moore's law, among other random internet articles, that modern…
Kenneth .J
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General "rule of thumb" for unused IC pins

This is somewhat similar to this question about NC pins. In cases where the datasheet doesn't specify what to do with unused IC pins, what is the recommendation to do with these pins? In particular I'm thinking of GPIO pins for the AT32UC3C…
helloworld922
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Odd markings on flash ICs - Are these factory rejects?

I recently purchased a really, really cheap SSD ($25.99), and I popped open the case out of curiosity. The flash chips have etched bars across the part numbers, something I've never seen before. Is this a standard way of marking chips as…
Connor Wolf
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Why would a Intel 8080 chip be destroyed if +12 V is connected before −5 V?

The Intel 8080 is a classic microprocessor released in 1974, fabricated using an enhancement-mode NMOS process, and shows various unique characteristics related to this process, such as the requirement of a two-phase clock, and three power rails:…
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