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Can a circuit board be waterproof enough to form a wall of a waterproof enclosure? Regular PCBs made of FR-4 with solder mask is what I have in mind. But I'm not barring less common PCB materials...
Is there a scientific way to estimate the resistance of a pogo pin? If it was a solid cylinder or wire one could calculate the resistance: R = ρ × L / A But a pogo pin is hollow inside, the sp...
I have an ordinary consumer-grade standby UPS with, I believe, ample power for the devices connected to it.[1] It's five years old. For the second time in about a month, I've found my computer po...
I benchtested below 0.7A constant current source circuit and observed few cycles of oscillation on drain current. With the help of bode plot analysis , I have managed to reduce the oscillations on ...
I have here an acre-counter or crop counter device like the lykketronic shown below, using two AA batteries. It arrived without working. Upon opening its case, I found that the PCB is missing tw...
I'm designing a robust 1-wire output for an IoT board. The interface should be able to withstand high voltage. Mainly the same voltage level as the board power supply. That's 12V to 36V DC. The p...
There are circuits that require matched transistors. Whether BJTs or FETs. Like current mirrors, logarithmic amplifiers, etc.. There are some examples: https://www.youtube.com/watch?v=DUlugLSroN8...
Hi, how can I use can bus monitoring through a simple led without disturbing the can line , I started with a diagram found on this forum, I need your help to correct where necessary, I want to use...
An important formula in physics is one that relates the speed of an EM wave (c for instance) with the magnetic permeability and electric permittivity of the medium. In short: - $$c = \dfrac{1}{\sq...
I've tryed to implement a local ground concept told by Olin Latrop here : He have told: (What I've perceived)You should not connect every gnd point instantly to gnd plane, since it can inject HF ...
Some gentlemen decided to throw a hook with wire over 750kV lines in Belarus. They survived, however, I find in interesting to find out why. Assuming the connection to Earth was solid, there would...
I have run into an interesting phenomenon related to ceramic capacitors. This question is part of the effort to understand the issue, and eventually work around it. But first, some background of ...
I'm Interested In Power Circuit. What Courses/Guidelines To I Need To Properly and Effectively Under Power Circuits??
I am currently learning amplifier design, after constructing the unity gain amplifier(which is a differential-input single-ended-output amplifier) in the unity-gain feedback configuration I have pe...
Hello! I would like to ask for your assistance with using a Silverstone DA1650 Gold computer power supply (you can find more about it here: Silverstone DA1650 Gold) for a non-computer application. ...
I was analyzing the design a hazard warning light.The spec of the light turn on off is given below. The flashing-light frequency shall be 90+/-30 times per minute. May I know in this case the...
I have seen multiple sources on the web discussing what they call concentric twist harnesses. It boils down to having a wiring harness built in layers, where each layer is twisted around the previo...
What effect does an oscillator potentially have on a SPI clk signal if the oscillator is on the top layer, with GND and VCC layer in between on a four layer board. I know running it on the same lay...
The remote control of my TV has two kinds of buttons. There are "normal" ones for the digits etc. which work by bringing a conductive material on the underside of the button in contact with the boa...
I want to know why the top-of-the-line CPUs and GPUs from Intel, NVIDIA, and AMD are all bragging about the fabrication process (7nm and 5nm) and trying to be consistently smaller. At the same tim...
Got a question about hazardous breakpoints in real-time firmware. Does C have a mechanism which lets me mark a section of code such that breakpoints are somehow ignored or not allowed just in that...
Based on reading the All About Circuits article on IEPE sensors there are two general types of circuits integrated into this class of sensors: voltage amplifier and charge amplifier. This question...
This graph - MLCC temperature rise vs ripple current RMS & frequency If I had a 10 us current spike every 100 000 us (akin to a half-sine wave and then the rest of 9999 sine waves missing), ...
EMG consists of an electrode gel skin interface, op-amps with a certain gain and an ADC. Question is in the context of passive electrodes. What are the essential safety features of such types of h...
I'm working on an energy harvesting circuit known as an in-house harvesting circuit (cc-ih) and would appreciate some guidance on implementing it in Simscape within Simulink. Circuit Description: ...
May I know how to calculate a signals rise time from it's frequency. I found this article for the same. The formula given is Tr = 1/f*π. May I know is this applicable for PWM also.
Do common-source JFET amplifiers have an advantage over common-drain? The JFET would be in a low noise photodiode amplifier. The signal is 100us pulses with 10us raise times. Here are the schema...
Lets say I power an oscillator by a non-rechargable battery. Lets imagine a generic design with LC-circuit and negative resistance created by some transistor circuit. To me it seems that at certai...
During the open circuit test of a induction motor ,not any current flows inside the rotor.But how can we achieve such a thing? Here is the ping configuration of a induction motor: The coils of ...
I’d like to create a stable IR LED light source. I’ve read that LED efficiency changes with temperature. I’ve seen two designs which used feedback through light to correct the LED temperature dri...
I've seen batteries get shorted a few times. They heat up, and obviously the battery is not useful after, but I've never seen them explode or catch fire. I've read reports of some batteries catchin...
Problem description & speculation about causes I've having a problem with MAX485 transceivers breaking intermittently, passing our production tests but later failing. The error phenomenon is w...
For high-speed digital communication busses, what attributes do you generally advise to add to a PCB to help with validating the communication bus as well as troubleshooting the design? In particu...
What is the concept behind the dynamic resistance that often pops up when dealing with non-linear components and the circuits in which they are employed? Is the concept related to other terms like...
Let's take a soft-start circuit that looks like this: To my understanding, the function can be described as follows: C1 charges to open the gate. Value of C1 will dictate the soft-start delay...
As the title says, I'm interested in a simple technique to measure the characteristic impedance of a cable using only the instruments available in a school lab or to a (somewhat advanced) hobbyist....
Do micro-RF connector mating crimp connectors are ever sold separately together with a crimp tool? For example this I have looked through a lot of pages, and can only find PCB connectors + cable a...
Suppose I have a planar PCB transformer. The primary and secondary coils are printed on different PCBs. The core is inserted through these PCBs to link the two coils. The primary is at a low voltag...
Question about relative humidity specification for electronics. Industrial automation, indoors, cabinet or instrument enclosure. The failure mechanisms at the upper limit are fairly intuitive. I'm...
I am working with an IC that uses a partially intergrated regulated charge pump. The circuit looks like this: It behaves like a voltage doubler. However, when looking at other regulated charge p...
I got a vintage ('64) hifi sideboard for Christmas! It's super awesome. However, I don't understand the grounding. It has two female inputs on the backside that are labeled as "Grounding". There w...
Power switches used in automotive are usually rated to withstand clamped load dump events, of the 35 - 40 V peak variety. AFAICT there are two main clamping mechanisms - first one for the logic par...
I am learning IC design layouts using Cadence Virtuoso and now I got stuck with the concept of using vias. The question is when and where to use it? I am attaching the schematic of my inverter tuto...
For my test bench I need an inductor (aka "reactor") that meets the requirements below. I have tried to purchase it outright as a made-up item, or the parts to make it (core and windings), but have...
I want to sense 3 different states in the same mcu pin (GND, Hi-Z and PWR). PWR is typical +24V but I would like to have a wide margin from +17V to +40V just to be safe. The values can change but ...
Building on a previous question about terminology, I am trying to arrive at a solution to connect a digital air pressure regulator that sinks current as part of its 4-20 mA current feedback loop to...
I'm working on another project with extreme EMC requirements as per various notorious military EMC standards. Civilian product but for military use, and as such subject to the toughest levels of co...
I would like to convert 5V rail I have on PCB to ±12V. Existing solution is using boost converter 5V to 12V, and a buck for 5V to -12V. This feels bulky for what it's needed - here are the requirem...
Hello, I am trying to use a CD4047 in monostable, positive-edge trigger mode: I am not skilled enough to make out what the output, i.e. pin 10, should be when pin 8, the input, is held at 0V (...
Mini-circuits LNA PHA-LN13+ has suggested: Eval board Layout Eval Gerber The image took from the Gerber file (3rd ref.) (Though all 3-reference mentioned containing it): There I have som...
