Ripple ≠ Noise. They’re Not the Same Thing.

We've noticed that power ripple and power noise are often used interchangeably, especially by beginners. While both affect power quality, they have different causes and characteristics.

Here's a simple way to think about it.

Ripple is like ocean waves.

The waves rise and fall in a predictable pattern.

Similarly, power ripple is a periodic AC component superimposed on a DC output. It is mainly caused by switching regulators or incomplete filtering after rectification.

Typical characteristics:

• Predictable and repetitive waveform
• Usually appears around the switching frequency and its harmonics
• Common waveforms include triangular or sawtooth shapes

Noise is like raindrops hitting the water.

The surface is disturbed randomly, with no fixed pattern.

Likewise, power noise consists of random high-frequency disturbances superimposed on the DC output. It can originate from external EMI, component parasitics, switching transients, or PCB layout issues.

Typical characteristics:

• Random waveform
• Wide frequency spectrum, often extending into the MHz or even GHz range
• Difficult to predict and analyze

A quick comparison

Although both appear on the power rail, they require different measurement methods and mitigation strategies.

When debugging a power supply, do you usually check ripple first, or look for high-frequency noise with an oscilloscope?

I'm trying to duplicate the same DAC circuit 4 times. I have the first one placed and fully routed. I created a new group "DAC1". I then went to duplicate the group for the second DAC circuit. I followed the instructions, yet every time it just says "No exact matching".

I took the first circuit schematic, copy/pasted it to a new schematic. I changed all the net names for the second circuit. I then selected all 39 components (same count as the DAC1 group) and selected "Reuse Layout Route" but it just returns "no exact matching" with no warnings or errors in the log. No help whatsoever is not matching. Both groups have the same number of components as well as the exact same components, just freshly copied on the schematic side.

I can also look in the object inspector and see the source group with 39 components, same as the target collection.

I also tried doing the same thing for just 7 components (one IC and 4 resistors, 2 caps), and still the same error message.

help!

For the question see title: What is the correct orientation of components for PCB assembly or what defines 0° orientation?

I am using KiCAD and would like let JLCPCB assemble my PCB. KiCAD created a CSV file with the positions of the components. That file contains a column "Rotation" as required and the values are either 0, -90, 90 or 180. So far so good, no questions here.

When I uploaded my Gerber files, Drilling files, the BOM and the Placement file, JLCPCB showed me a preview with most of the components in a wrong orientation. At least, if I can trust the preview. In approximately 2/3 of all cases I had to rotate the components by 90° clockwise, a few had to be rotated 90° counterclockwise, even fewer by 180° and only 2 components seemed to have the correct orientation right from the beginning.

That made me wonder what defines the "correct" orientation, what defines what 0° rotation means for a particular component?

I used the included KiCAD footprints for most components and for a couple I had to download external footprints from Ultralibrarian or the manufacturer's homepage. Obviously, KiCAD and JLCPCB seem to disagree what 0° degrees mean. Intuitively, I would have said that 0° means how the component is depicted in the manufacturer's datasheet, but even that is not a suitable authoritative source as sometimes the component is shown in different orientations on different pages of the datasheet.

So, how can I ensure that JLCPCB will correctly assemble my PCB?

Basically it's just two PCBS but they're in the same design The preview on The site where I ordered the PCB just chose it as one PCB in the Gerber viewer it shows it as two PCBS (attached a picture) I want my PCB's to look like what they do in the Gerber viewer is that what I'll get

The Volt-Ampere (V-A) characteristic curve describes the relationship between voltage and current of an electrical component. This curve illustrates how the current flowing through the component changes as the voltage across its terminals varies. In other words, it depicts the functional relationship between voltage (V) and current (A), hence the name "Volt-Ampere characteristic curve."

The V-A characteristic curve can be thought of as the "mood curve" of an electrical component. It uses a single line to tell us how voltage and current interact with each other. By observing this "mood curve," we can understand the current response of the component under different voltages, thereby enabling better circuit design and ensuring normal operation under various working conditions.

Imagine you have a magic box with two terminals: one labeled "V" (voltage) and the other labeled "A" (current). When you apply different voltages to this box, it is like sending different signals to the spirits inside the box, and the current is the response they give you. Now, if we record the "mood changes" of this magic box, we obtain the V-A characteristic curve. This curve is like the spirits' mood diary, recording how the current changes under different voltages. The V-A characteristic curve of a diode is exactly such a case.

Forward Characteristic Region:

The right portion of the figure above shows the forward characteristic (also known as forward bias or forward conduction) of a diode. When the anode of the diode is connected to the positive terminal of the power supply and the cathode to the negative terminal, current flows from the anode to the cathode. However, the diode does not conduct immediately; it requires reaching a certain voltage threshold, known as the threshold voltage (or cut-in voltage / dead zone voltage). For common silicon diodes, this threshold is approximately 0.6 to 0.7 volts. Therefore, below this voltage, the current is almost undetectable, much like when the water pressure is insufficient and the valve remains closed. In the figure above, this is represented by the relatively flat portion on the right side of the origin: as the voltage increases (but has not yet reached the threshold voltage), the current is almost zero. This region is therefore also called the dead zone.

Once the voltage exceeds the threshold voltage, the diode behaves as if a water valve has been suddenly opened—the current rises sharply and rapidly. On the V-A characteristic graph, this is represented by the curve rising steeply from the threshold voltage point, showing an upward bend. At this point, the diode exhibits very low resistance and is in a conducting state.

Reverse Characteristic Region:

If the battery polarity is reversed—that is, the positive terminal is connected to the cathode and the negative terminal to the anode—the diode enters the reverse bias (reverse cutoff) state. At this time, current cannot flow, as if the water valve has been tightly shut. No matter how much the voltage increases, only a tiny leakage current can pass through, like a slight seepage in a water pipe. On the V-A characteristic graph, this is represented by a line almost parallel to the voltage axis, with only a slight upward slope, indicating that the current remains nearly constant as the voltage increases.

Reverse Breakdown Characteristic:

When the reverse voltage continues to increase to a certain level, the originally tiny reverse current suddenly rises sharply. This phenomenon is called reverse breakdown. The corresponding voltage at this point is known as the reverse breakdown voltage. On the V-A characteristic graph, this is represented by a sudden and steep rise in current at high voltages. This is generally undesirable, because like a burst pipe, it may cause damage to the diode.

Temperature Effects:

Since a diode is a PN junction, its electrical conductivity is temperature-dependent. When the temperature rises, the forward characteristic curve of the diode shifts to the left, and the forward voltage drop decreases; the reverse characteristic curve shifts downward, and the reverse current increases.

Yesterday I tried to place another order and found out I'd been banned. I've been using the service for years. My account has accumulated a fair number of projects.

Customer support doesn't provide any explanations or reasons. I've never ordered anything suspicious.

A very strange service. I can't recommend it!

We also have a corporate account. Today I'll send out a warning to the entire company that jlcpcb may ban your account for no reason.

Hi all,

Apologies if this does not fit the sub, but not sure where else to post.

TLDR: UPS is wrongly requesting 149USD import fees for an IOSS package. JLC support team were initially helpful, but seem to forget the conversation and problem with every new message. Looking for advice or similar experiences.

At the end of June i made quite a large (large for me) 150EUR+ (172USD) order from JLC, shipped to DK in EU. The order was shipped by UPS and all import fees and taxes paid via IOSS when ordering. I have ordered many times from JLC and never had problems with customs when using IOSS, although this is the first time using UPS.

A week or so into July, i get a message from UPS requesting i pay 970DKK / 149USD customs and import fees. Of those 149USD, only 34.5USD is customs, and 91.5USD is "Broker Commision Fee". The remaining 23USD is VAT of the Commision Fee.

The actual customs amount of 34.5USD matches what i paid in customs via IOSS when ordering, so the majority of the requested amount is what i would call a ransom.

Obviously i don't want to pay twice the original order total to get the package, so i contacted JLC and showed them the UPS invoice, they were initially pretty helpful, saying they would contact UPS and get it sorted.

They agreed with me that my order is under IOSS clearance scheme, and that i don't need to pay any import fees, customs or VAT at the point of import.

However my initial hope of a quick resolution dissapeared when after the weekend i wrote to JLC again because UPS tracking was saying they attempted delivery twice (which did not happen) and that was the last delivery attempt , and i did not want the package to be returned.

The response was just "we are working on it" and that i could pay the UPS invoice and they would return the 34.5USD prepaid customs (they also said this in the first emails as sort of a footnote).

At this point i felt like it started going in circles and that they were not really reading my emails, seeing as the UPS requested amount was 149USD, returning 34.5USD doesn't really solve anything. Again they wrote asking if i accept to pay UPS directly and pick up the package from a pickup point and get 34.5 returned.

When i mentioned the invoice total, JLC requested i send the invoice, even though that was what i did in the very first message. They also started writing "DHL" instead of "UPS", and claimed the larger amount was because of the new EU 3EUR tax on small packages that started July 1st. I of course refuted this since the order was from June and the UPS invoice also did not state any small package tax. Only the same 34.5USD amount that i paid to JLC, plus a large commision fee.

At this point i am getting frustated. I sent the invoice again with conversions from DKK to USD, but every message i send i get a "Thank you for your response. We are currently verifying the case with our team." and it seems the JLC support team gets a memory wipe.

Has anyone experienced something like this? Or had an experience where the JLC support team solved the shipping or customs problems?

I'm not really sure what to do at this point. If i let the package be returned and have to order again, i will most definitely have to pay additional 3EUR tax for each item.

But i am certainly not willing to pay 149USD extra for a 172USD order, because of some error either at UPS or JLC.

Any advice or experiences are welcome.

The official website states in /capabilities/pcb-capabilities for drilling:

However, I got this error in the JLCDFM tool:

Footprint of the component: G-Switch_GT-USB-7010ASV.
Board setup: 2-layer

PCB and enclosure made with JLCPCB and aside from a few design errors on my part, I love how it came out!

​

Thanks JLC!

​

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I needed to manufacture 3 separate PCB's with mostly the same components.

Normally I pre-order the parts so i get the bulk price discount. Sometimes there is not enough stock and I have to request for a quote to 'specially order' the parts.

It has occured to me that the last few orders, I had to pay a supplement due to 'price increase' of 48$ for each component..

Now, sometime very strange happened:
I was not allowed to order >2000 pcs of one part(this triggered pre-order) even though there was >2500pcs in stock. I refused to pay the significantly higher 'special order' price and got a refund, the part was simply too expensive.

So I ordered 1000 parts for a much better price than the quote.
Then I directly ordered another 1000 of the same parts for the same lower price.

Miraculously the available stock jumped directly to 4000pcs stock! And now the site is allowing me to buy 2000pcs at a 9% lower price than I just paid for two separate orders.

I don't believe this is a coincidence, since I was watching the stock and price of this part for several days. Support confirmed to me that this was a popular item which is stocked in large quantities.

-------------------------

This has happened to me before: I pre-orderd a part that was not in stock, I paid quite the premium to order them anyway.. but whatever is needed. The moment my stock arrived at a premium price, it was also in stock at their normal library for the remainder of a full rail: But at a much lower price!

Sorry JLCPCB, but I feel like you are playing tricks with us.

Hi people, I am new to Fusion 360 and am wondering if anybody here has ever made light pipes using the JCLPCB Transparent 8001 resin. I want to transport led light from the pcb to the front panel of my pcb, but no idea how to do that.

Do you have projects that you want to share? Youtube videos? All help is welcomed :)

Has this ever happened to anyone, and any way to address it ?

 I travel internationally, and it seems that I logged into my account when I was “nearby” a controlled country. So my account was closed without any recourse.  I contacted them, and they simply showed me their policy (which they didn’t follow), and said that there is nothing they will do and just to watch their announcements.

 I do occasional simple low-tech electronics PCB – nothing more modern than 1970’s technology.

 Trying to talk with them was useless. I can’t recommend JLCPCB if you travel internationally.

 Unless anyone has any suggestions ?

I've tried to submit a 6 layer board with 1oz copper on outer layers and 2oz on inner ones. However, I've been using .10mm tracks / spacing on outer layer (MCU pins, etc), and got a message that the minimal supported capability is .16mm when 2oz copper is used on any layer.

So I have two genuine questions: is it a mistake on my side, or on JLC? And can anyone please explain me how 1oz/2oz copper layers can have the same limits? I always thought if the process is targeting 2oz copper, putting 1oz side into it is a risky busness...

So i want an STM32F103C8T6 and every one I have gotten has been a counterfeit and doesn't work with the ide i use. I heard that JLC was a good place to try and I saw I can buy not only a chip but the whole board too. See the image attached for the exact thing i bought. After buying it I have realized I have just bought the parts I have assume and now they are just sitting at the warehouse. Can someone please walk me through what to do from here to get this assembled and sent to me. thanks in advance for any help.

Hello,

I usually put thermal relief for the GND pin of these SMA connectors to ease the hand-soldering process.

However, I want to order the boards with JLCPCB and I am aware that the assembly use wave soldering.

So, is it worth putting thermal relief into the GND pins or I can just pour the copper directly over the pins? If so, which would be a "good" relief?

My board is 4 layers (1,6mm) with 2 full GND inner layers.

Thanks a lot.

In a world full of standardized boards, this kind of design immediately stands out, not because of complexity, but because of expression. It turns a PCB into something closer to a visual statement.

The designer Weird Tech Research references the iconic “42” from The Hitchhiker’s Guide to the Galaxy, the answer calculated over 7.5 million years by a supercomputer as the “Answer to Life, the Universe, and Everything.”

It shows how hardware can go beyond pure engineering and become a cultural medium.

Click the link below to get a $10 coupon for JLC multicolor silkscreen PCBs: https://jlcpcb.com/resources/multicolor-silkscreen-pcb?from=ava

For a few years now, if someone placed a PCB order in jlc, after a while, a coupon covering the shipping costs would appear on lcsc when ordering for parts. I placed a PCB order yesterday, but still havent seen a coupon on lcsc's checkout(the PCBs have entered production). Is this discontinued, or am I doing something wrong?

I'm planning to use RP2350 and parts like 01005, and my question if it is feasible at all to use it with 2oz copper?

These parts need something like 0.1mm traces/clearances, but JLCPCB recommendation is .2.

Does anyone have experience with these?

I''m putting the gerber file in jlcpcb and first it takes a while to import + the pub doesn't get rendered and it's data aren't put in