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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...
I have had my soldering iron tips degrading at ridiculous rates. Granted, they are not very expensive, but sometimes it takes less than 8 hours of soldering for them to degrade to the point where t...
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 have a handheld ARM Cortex M based device, which has a USB input port. The product is battery powered and there is no metal chassis. We are going through CE testing, and are having ESD issues a...
I read datasheet for PCT2075 temperature sensor and there are some contradicting data about accuracy for me. Page 21: accuracy ±1°C (Tamb = -25°C to +100°C) accuracy ±2°C (Tamb = -55°C to +125°C...
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...
In this bistable multivibrator which is $Q$ and which is $\overline{Q}$?
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...
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...
Problem Description I am trying to design a BLDC inverter and I am in doubt of what would be the right approach for estimating the input capacitor size/type. Doing it empirically or throwing every...
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...
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...
I always have a doubt that how do firmware engineers dump code into a quad flat microcontroller? For a starter kit there is already connection like USB or some SPI ,I2C headers to burn the code,als...
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 ...
I am trying to test a AD8307. Here are my connections: (pins not shown are left unconnected, and also pin 8). I get a quiescent output voltage at pin 4 of about 850 mV with respect to ground, w...
Here is a video of the AN/PRM10, and here is a schematic (I believe the image can be zoomed): As most commercial grid dip meters produced in the past, this one possesses several functions in ad...
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...
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 ...
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...
I have a question about this circuit:(critically damped oscillation) For a critically damped oscillation for a series RLC circuit the equation of current has this form I(t)=D1te^(-at)+D2e^(-at) ...
Simple thing that I realized I should know but do not -- when is an MOV preferable to a TVS diode (with some associated network to really make it work, in both cases)? Is it even something to routi...
I am trying to build an active-low digital isolated switch capable of withstanding 32VDC voltage without creating any damage to the system. This is the snapshot of the circuit not fulfilling the r...
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 (...
The display counts range is one of the digital multimeter characteristics. We know that a DMM is based on an analog/digital converter, and we know too that each ADC has a certain resolution in bit...
Imagine a battery pack with <=60VDC of maximum voltage and a load of up to 10kW of power(the PMSM inverter with the input capacitance of up to 1mF). The load is not always known - could be 100uF...
I've heard that a bootloader is code that runs on a microcontroller, and is used to get your application code onto the micro. How does that work? Is there anything special that needs to be done to...
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...
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...
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'm trying to drive a relay according to a 5 V digital signal, using this circuit: It works for a while, but then the transistor fails. When I replace the transistor, it works for a while again, ...
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...
What is the relationship between the pole zero diagram and bode plot? Case example: a 2nd order RLC low pass filter: - $$\dfrac{V_{OUT}}{V_{IN}} = \dfrac{\frac{1}{j\omega C}}{R+j\omega L +\frac{1}...
Sometimes cables between utility poles make a loop and do a U-turn. What is the purpose of such loops? The loop I'm asking about is in the lower set of wires towards the left of the picture. The...
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 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 ...
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...
I'm using a variable duty cycle square-wave oscillator to drive a half-bridge MOSFET pair like this. Upper MOSFET is P-channel type, lower MOSFET is N-channel type: - And, I think I'm getting shoo...
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...
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...
Since am interested in how a delta sigma modulator works, I need to know what is the difference between differential amplifier and differentiator if there is a difference of course.
When should I consider using RTOS in my application? Every microcontroller has a good number of interrupts then what is the need of it?
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 have no record in electrical engineering; this is a total outsider question which might be grasped absurd. Wikipedia defines EMP as: An electromagnetic pulse (EMP), also sometimes called a tr...
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...
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...
I am really confused how the terms bit-rate are baud-rate are used in electronics. I never bothered thinking about baud-rate being different than bit-rate before. But recently, one of my teachers t...
I have seen pi-filters using chokes, ferrite-beads, and plain inductors as the L-element What are the main differences between them? when use one or other?
[I’m asking this question out of curiosity. I understand that this aspect of the CAN bus specification is what it is, and can not change.] The ACK bit in any CAN data frame is dominant. Each rece...
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...
