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Nowadays, that I videoconference over WiFi a lot, I've started to notice some trends in WiFi quality. And it seems my connectivity decreases when my microwave oven is on (I work in the same room a...
In the past, a large number of new active building blocks have been proposed and published by many researchers all over the world. In most cases, these new building blocks were used for realizing n...
What happens to the overall accuracy of a resistor if I implement it as multiple resistors in series or parallel? For example, can I get better than 2 kΩ 5% by putting two 1 kΩ 5% resistors in ser...
I don't know whether this question is on-topic or not but answering this helps a lot of future electronics entrepreneurs like me understand how the product design and development time estimation ta...
I've heard that input signals to digital circuits should be "de-bounced", at least sometimes. What is de-bouncing? Why is it needed? When is it needed? What is bouncing around in the first place?
Introduction: In some books and other technical papers (also from universities) it is - surprisingly - still claimed that the bipolar transistor (BJT) would be a current-controlled element. This is...
We see schematics of varying quality and conventions. What is good and bad? What are the rules and conventions for drawing good schematics? What matters? What doesn't? This question is about sch...
The output collector-emitter part of a transistor can be thought of as a 2-terminal SPST switch controlled by the input base-emitter voltage or base current. So this transistor switch can control o...
I'm curious about FPGAs and would eventually like to get into them sometime during the future, so I'd like to ask three broad questions to help orient myself: In what applications are FPGAs the m...
How exactly is the emitter capacitor C3 helping to increase the voltage gain in the common emitter amplifier below? Is it because for AC signals the emitter looks like a short to ground and that es...
There is always a mixed response when comparing power management ICs (PMIC) and microcontrollers in the application of power converters (I mean as pwm controllers). What are the advantages and dis...
It is well known that it is difficult to filter the noise generated by switching power supplies, and this difficulty increases as the PSU is supposed to deliver large currents. For example, in a us...
In theory (I mean in my engineering curriculum) I never found a diode in a mosfet symbol but in datasheets there is a diode called as body diode in both pmos and nmos.Please explain its significan...
Although I have done multiple PCB designs which passed FCC and CE equivalents using the MCU's/Multiple MCU's, I have a doubt about how to approach the high speed design using FPGA SoC - main thing ...
In a lot of textbooks, filters seem to be designed around a matching source and load impedance. However, If I have a filter stage between an antenna and an LNA, wouldn't I want the load impedance(i...
Moderator Note If this site were mature, this question would be closed because it solicits opinions, or is too specific about particular models. In the interest of site activity, answers are being...
I want to make a simple 7MHz direct conversion SSB receiver in order to materialize some RF concepts I have been teaching myself lately. My question revolves around the mixer portion. I'm failing t...
I have seen many engineers talk about ESD protection but I had never seen its effects myself. I made many small DIY projects and I have used bare hands to touch ICs and their pins,but nothing got d...
I see a lot of common collector amplifiers with the output taken across an emitter resistor. What is the purpose of doing it this way instead of connecting your load directly to the emitter? I sh...
I was looking at this design: It uses MC34063 as switching controller. I wanted to adapt this circuit, and I was busy trying to pick R1 value. The datasheet has following formulas: The issue I hav...
Despite there are many filter calculators available on the web, I still have difficulties to translate what I need into calculator design parameters. For my application, I need ideally a high pass ...
I want to include a wirelessly charged battery pack into my design. However, I am worried that the wireless charging could damage my main logic board. What considerations, apart from not having loo...
Why do we use open collector / open drain configurations in circuits? From one source I learned that LED controls are of two types- (1) Push pull,(2) Open Drain.Why do we use and what is actually h...
Here is the bootstrapping technique for opamps, as exposed in the Art of Electronics:. This technique is supposed to increase considerably the input impedance of the opamp for an AC input source (...
I always had trouble understanding the terms "digital" and "analog"; Wikipedia and various Q&A sessions didn't contain explanations I found clear. I understood that these terms aren't well defi...
Hello, I am designing 1/4 WL strip antenna for a bluetooth chip and i had some questions regarding the 50 Ohm feed line. Right now I am using a Nordic-recommended 1.5mm trace width and a 23mm + 4mm...
I have a MAX809 with RESET pin connected to the gate of IRLML6344. I will rephrase my question. At 5 V, RESET is also 5 V and the LED lights up. But if I add the fan, RESET drops to 0 V and draws 1...
Consider this statement "A voltage source is heavily loaded",what does this mean? I mean that whether the load resistance is high or there is huge drop in source voltage at load due to internal res...
I am having a difficult time picturing the flow of current and the role of the capacitor during the OFF time of a buck converter. Here is my understanding so far. During the ON time the magnetic fi...
I've been experimenting with LC filter circuits on the output of a SMPS I recently bought because it was too high for the circuit I'm making. After hooking up many different combinations, I found t...
It is common to have a series resistor to limit the current trough an LED. I saw a circuit using the LED driver: stp16cpc26. but instead having the series resistor, they are in parallel. This LED...
This is an energy meter reference design guide I found in microchip's website. In a microcontroller how come the registers are specific to the project?Please explain.
Recently I had opened an remote control (RC) toy to see its circuit and found that it operates on 27 Mhz. Not just that toy even many toys operate in that 27 and 49 Mhz band. These days we find eve...
I am designing a 4-layer PCB that has both analog and digital circuitry throughout it. The analog section involves high return currents as well as ADCs sampling the voltage across sense resistors a...
I was watching this video by w2aew on the function of ceramic bypass capacitors, and at 6:00 he states that high-frequency currents take the path of least-impedance and make their way to the power ...
Hi, I built a constant current load following the circuit from https://www.instructables.com/id/DIY-Constant-current-load/ But my op amp gets destroyed after a few minutes. The transistor or the op...
Why does the Darlington or Sziklai configurations need complementary transistors? For these configurations, when should I use complementary pairs and when could I use not complementary pairs ?
I understand that some applications require NPN-PNP pairs with identical electrical characteristics. But I would like to understand why.
This application note from Linear Technology discusses oscillations in opamp circuits and some compensation schemes. One method discussed for reducing phase shifts in the loop gain due to the RC ne...
Recently, my home suffered a partial power outage, and due to curiosity and a desire to learn more about residential AC power, I'm trying to understand how the event that took place resulted in the...
Hello. I have a grounding problem on my acquisition system. I have read many articles, app notes and whatever but still could not find a convincing solution for the topic. The acquisition system is...
Certain high voltage resistors are fairly hard to get, such as the HVR37 series from Vishay. I'm looking at redesigning a board that produces 1000V via a transformer, but I want to use parts that ...
I've accidentally burnt my dimmer with a short. It is a common dimmer with a triac/diac/pot of the simplest configuration (the triac is a BTA16). After replacing the triac, this still does not work...
I am designing a PCB that has to have class 1 div 1 associated apparatus (only the outputs to the sensor) certification. Essentially, I am using a boost converter to convert the voltage from a lith...
A few decades ago, I found a digital circuit that squares a 4-bit input in an old textbook (perhaps 1970s or 1980s). (The figure below is not the original. It differs from the original in that it ...
I need to design a simple flyback converter like this: - I want to control duty cycle from another circuit such as an MCU but, I'm unsure how to proceed. My requirements are: - Input voltage 125 ...
My step-up converter makes audible noise both with and without a load.I am almost certain it is the inductor, because when I hold my finger on it I can feel vibration and it gets quieter. Unfortuna...
What benefit has a differential amplifier when measuring the signal from a sensor that is remotely located such as in this example: - Why can't I use an arrangement like this: -
I've built a non-inverting op-amp amplifier with a gain of 101 using this circuit: - My input is 10 mV DC and I expected to measure 1.01 volts at the output but I measure 0.81 volts. What has happ...
