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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...
Consider a device with a microSD card. The microcontroller writes to the SD card periodically. The operators have an ability to remove the microSD card at any time (they will be removing it every...
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...
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...
In a general sinewave as below, is there a "right" way/"standardized" way to measure line frequency - and how do energy meters calculate that? measuring pulse width of half-period, ie. time elap...
I'm having trouble using the nodal equations to determine the base voltage Vb1 in the circuit below. I've attempted to write seven equations below, but not able to fit them in entirely. (12-Vx)...
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 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 own understanding I tried modelling switching off an inductive load without a freewheeling diode to observe ringing. This is the model I used: 1.) Are the two main components of the reson...
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...
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...
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'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...
A circuit under question: Why are CY capacitors on the source side, and not on the load side? Henry Ott describes this with: “Because filter attenuation is a function of impedance mismatch, th...
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...
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...
Most CAD packages use a "symbol" and "footprint" library approach when it comes to designing schematics and PCBs. Some (like recent versions of Altium) have "component" libraries where symbols and ...
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...
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 am determining the Area-Product of the core required for a transformer to be used within a series resonant converter. The specifications are as follows: Switching frequency = 400 kHz Primary ...
Hello,i need to drive 5 mosfets as shown below. Each mosfet draws 15A when the pulse opens the mosfet. My power supply is gives the 48V but only 3.3A,If I understand correctly I need to put very...
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 ...
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...
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...
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...
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...
I understand that white noise is not always Gaussian. In general, is the $V_{pp}$ and $V_{RMS}$ noise stated in operational amplifier and ADC datasheets Gaussian? And is its mean zero? Any exemptio...
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 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...
Why can the channel capacity C of the additive white gaussion noise (AWGN) channel be denoted in different ways and how do they relate to each other? Examples: C = (1/2) * log2(1 + SNR) [bit?] ...
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...
Hello,I want to simulate a delayed pulse going from 74ABT04 to the load which is UCC5304 where load with 400K i think. but my pulse source 74ABT04 is not an idial voltage source as shown in the s...
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...
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: ...
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...
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...
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...
Hello, I want to understand the math of the phenomena of capacitor as temporarary means of increasing the current supply. First I have created a current limited voltage source which give me 45V a...
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 am studying for a test in control systems and we have a practical part which is to program a analog computer. Here is a picture of the analog computer: The variable resistor is basically a vo...
This picture describes the behaviour of a single phase transform under resistive,inductive and capacitive loads(from left to right) How what exactly is $V_{1}$ ?Is it the voltage at the primary ...
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 ...
*Learning about EMG as a part of our research. My team has at least some experience with electronics that is worth mentioning, but don't have any experience with EMG/bio-potentials. Most EMG hardwa...
I am working on routing a microprocessor to two identical single data rate (SDR) SDRAM chips that are PC166 compliant, particularly Alliance AS4C16M16SB-6TIN. The 16 bit SDRAM chips are combined t...
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...
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. ...
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 ...
