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Measuring the resistance of water from my tap I got 500kOhm. Adding considerable amount of salt brought it down to 20kOhm: The question I have is why water is such a danger for short circuits if t...
How can I acquire electronic parts/items/modules and ensure that there is minimal risk of them being unsuitable for my project or design?
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}...
I need to design a simple boost 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 12 vol...
I have a signal at 10 MHz produced from a 50 Ω source. How can I match that to a 300 Ω load with low losses without using an RF transformer (space constraints)? Are there any circuits and formulas ...
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...
When switching a relay there should be a flyback diode. It could be just a diode or diode with resistor in series. I understand there is a difference in the speed of relay switch-off. But what is t...
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...
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...
I understand that some applications require NPN-PNP pairs with identical electrical characteristics. But I would like to understand why.
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...
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.
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 (...
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...
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...
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?
I thought I understood the theory of scattering parameters, smith charts etc. until I tried a practical example. The following stupid example is supposed to be a microstrip line shunted by two 100...
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...
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...
I am looking at the datasheet of the 7508170315(link) transformer and something seems strange to me. If I connect this to a 12V supply and expose it to 10us pulse: 12V*10us/475uH = 252mA which ...
In the image below is an opamp buffer with +/- 15v rails connected to a 3.3v ADC. The input to the opamp is limited to 0-3v. There is no protection circuitry for the ADC. Is the risk of the opam...
Every time I needed CAN, I had just put external crystal and didn't think about it after that. It worked fine. I am wondering however whether the precisions of MCU internal oscillator is sufficien...
In the circuit below, I am applying a $3.3Vpp$, $63kHz$, 50% Duty Cycle, PWM input signal at the gate of the mosfet and I am expecting to see a similar waveform with different amplitude at the LED...
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...
Background: I have several microcontroller based projects with custom PCB that have been in very-low-volume production, but the quantities are starting to go up. (batch sizes now ~100 and threateni...
Sensorless BLDC motor controller are becoming more and more popular, especially with rising of the drone industry. Being able to detect where the rotor is at 0rpm or no load seems intuitive if we ...
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 have a 900MHz radio with a reference design matching network. The radio feeds to a PCB antenna (PCB antenna hasn't been verified with a VNA, and may not be a great match; this is a project to n...
Small-shop question here. Is there a convenient tool for making the bend shown below, other than a pair of pliers that happens to be just the right size, and is it worth it for qty low 100's? ...
In the design of a power converter, picking the appropriate capacitors for the input and output of the converter is quite important. It is relatively easy to calculate the necessary values for a gi...
I have a battery pack that consists of 18650 battery cells(14 cells in series max.). Hence, the voltage of the battery pack will be between 35V and 60V(to be on the safe side) I am designing a BMS...
How does the differential to single ended converter work? In order for the circuit to work, Q1 and Q3 must be in the saturation region and depending on the voltage inputs, one of Q2 and Q4 will be...
Suppose we have this circuit which is supposed to be an unbalanced frequency mixer. But how does the diode generate a signal with new frequencies at the output?
In noise analysis of operational amplifiers, the following is considered: Noise generated by the external components (resistors in feedback network etc.) Noise generated by the operational ampl...
I was looking at the video of the Tesla Model 3 motor controller(400VDC, 500A) disassembly and noticed a resistor network as in the picture below. They are 2k resistors(SMD code 202). See the pic...
In this bistable multivibrator which is $Q$ and which is $\overline{Q}$?
Based on this paper on Wiki a diode can be described as a frequency mixer due to the exponential relationship between current and voltage.What I don't get from which point to which point do we meas...
Suppose we have this circuit How do I pick a appropriate value for the resistor R1?
I'm wondering if there are particular aspects of an oscilloscope probe's performance that tend to suffer, or failure points to look out for, if/when buying lower-end makes of oscilloscope probes (l...
Can we find the internal resistance of a multimeter ,when we use the multimeter like a ampmeter, from its datasheet? I am trying to find the internal resistance of IDM 505 and I went to the datash...
I have designed a PCB that I need to work in which a microcontroller drives a 24 V brushed motor. The input power to the board is 24 V, this is then lowered to 5 V by a step down converter, and thi...
Which important system design parameters need to be locked in order to estimate the maximum allowable level of the input voltage ripple of an SMPS? I have encountered ballpark figures of <1%, &...
I have an mcu pin and I want to sense a voltage up to 24V to 36V. I want to connect some outputs on the board I'm designing and I don't know whether those outputs will provide a voltage or will be...
The submarine built by OceanGate went missing on 18th June 2023. A lot of online criticism was directed towards the control hardware of the submarine - Logitech F710 controller. However, why i...
Let's say a 100V voltage spike arrives at +12V and the TVS diode clamps it to 25V. Q2 may or may not be activated. Will this circuit ensure a V_gs lower than 25V for the mosfet Q1 ? Any catch to it...
When recording an ECG signal, the raw signal is taken from the body and sent into an ECG amplifier to amplify the signal to a suitable range and remove common mode and other types of noise. Measur...
A full wave rectifier converts a sine wave to DC pulsed signal of double frequency. Is there a circuit which does the reverse process?
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...
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 intend to build a high-power series LC resonant circuit for the purpose of generating strong magnetic fields at a wide range of frequencies, mostly audio range (1-5000 Hz). The inductor coil is a...
