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I have an opto-coupler circuit where is very slow turn off. I can't figure out what is the cause of this problem. It's for UART isolation, with speed 9600 baud. Datasheet: EL357NC Do I have som...
I have a bed for which the headrest can be adjusted. There are 2 separate power inputs for each side like in the picture: In addition, there is a set of 9V batteries on each side, presumably for...
I don't find any of such cables, and the discussions on the web revolve around SATA being point-to-point and not designed for networked or shared storage. However, if one'd build a cable that is j...
Hi All! I've been looking at how to perform active battery balancing, and I'm currently struggling to understand which type of transistor to use to act as the switch for the "balancing capacitor"....
This problem investigates the behavior of the voltage across the capacitor in response to a step input: - I am asked to find the voltage Vc(t) without the use of differential equations or simula...
Rosenberger 23C25D-40ML5 specifies 500V RMS rating: Looking at the recommended landing pattern you can see that the distance between the signal landing pad and housing of the connector is 0....
Hi All, I have a query regarding the cable sizing and motor starting. I have a 200HP motor to feed Low voltage power @480V. The distance between the substation and the motor is 2000m. Voltage dro...
What are closest free or low-cost alternatives to software like Ansys PCB modelling? https://www.ansys.com/blog/optimize-your-pcb It's too costly for study purposes. To clarify: I am looking fo...
Do I need to consult FCC regulations in order to modify a laptop's internal WI-FI antennas to a new housing? This is quite common when modifying laptops to "slabtops". For example, one could 3D pr...
When posting identification or general questions related to connectors, integrated circuits or other parts with pins/legs, engineers always speak about something called pitch. What is the meaning ...
I'm trying to implement a circuit I read about in a book recently, but having a hard time deriving the relationships for the required impedances for error corrector balance. Here is the circuit: ...
Reading a Tesla Wall Adapter installation manual , their brand of an AC EV charger, chapter about “Ground Assurance” and here is the quote from there: Although the equipment can work with L1 and...
I'm looking for a power supply to power up the VCORE of an mcu. The chip is an STM32 microcontroller (LQFP) and the maximum current it will draw is no more than 150mA. The input will be 3V-5V max...
I am reading through a multi-channel power supply manual and at some point it discusses the ability to chain channels in parallel to increase current output. In the schematic, there is one resisto...
As a personal project, I have designed a synchronous FIFO in Verilog HDL. But while testing with a testbench, I observed that the FIFO values are flushed out after one clock cycle when read-enable ...
I have a PIC18 and I'm trying to detect whether it is connected on the CAN bus or not. When the PIC is not connected on the bus, and I load the transmit buffers, after setting the TXREQ flag. The ...
I've got a is self-powered USB device, which means that I have to do VBUS detection. The device is built around STM32G474. Unlike some other STM32s, the STM32G4 don't have a dedicated pin for VBUS...
I want to operate a BLE chip at very close to its absolute maximum voltage. The chip is nRF52810 This is intended for a battery powered device and I want to use a 3.6V non-rechargable battery dir...
I was reading through the datasheet of a boost converter, TPS61023 from TI. In the "Input Capacitor Selection section", they give the following advice: 8.2.2.5 Input Capacitor Selection Multil...
I am looking at this RF connector. I see that insulation resistance and breakdown voltage are specified, but no voltage rating: I have two questions, one functional and one safety. Functionally...
We have ESD tables in the laboratory with Earth Bonding Points: These are directly connected to PE (I measured). It is my understanding that equipment has to be connected to PE directly and ESD m...
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, t...
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...
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...
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'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)...
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...
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...
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'm Interested In Power Circuit. What Courses/Guidelines To I Need To Properly and Effectively Under Power Circuits??
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...
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.
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: ...
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...
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’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 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...
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 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...
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...
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...
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...
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 ...
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 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 ...
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...
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...
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...
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...
