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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...
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...
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...
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...
I understand that some applications require NPN-PNP pairs with identical electrical characteristics. But I would like to understand why.
I used to live in the United States, and my microwave ovens' turntables turned at six rotations per minute (RPM). I now live in Israel, and my microwave oven's turntable rotates at five RPM. Annoye...
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...
Application notes for microcontrollers or other ICs that have an internal 10M/100M ethernet PHY module differ in their requirements for the external interface components. It seems that the PHY des...
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...
Assume my oscilloscope is grounded, and the DUT is grounded as well (earth ground). I am using a standard 10 Mohm impedance 1:10 passive probe. So, the ground terminal of the probe is in fact con...
While doing some reading on RF designs I ran across this paragraph: I have never designed an RF circuit, but all the PCB trace antennas I have seen on development boards are square. For example,...
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...
In the field of DC/DC conversion, one can build a synchronous DC/DC converter (also referred to as synchronous rectification). This practice involves replacing a diode with a MOSFET switch. As far...
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 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...
A differential amplifier amplifies the difference between the two input voltages but suppresses any voltage common to the two inputs. Based on this scheme the differential amplifier is substrac...
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...
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...
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...
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}...
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...
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...
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 ...
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 want to run a specific motor in the open loop. How to calculate the maximum ratio of V/f to run it? Am I looking at Ld or Lq value for this? Let's say these are the characteristics - haven't ch...
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...
When soldering Micro-USB or USB-C connectors by hand, flux is applied generously. This sometimes results in flux getting inside the connector housing, making it sticky and creating high physical re...
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...
If you search through the electrolytic capacitor offerings from distributors like Farnell, RS, Digikey or Mouser, you find that the maximum life-time rating is commonly quoted as 5,000 or 10,000 ho...
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...
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...
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 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...
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...
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.
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...
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: -
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...
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 ...
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...
How can I acquire electronic parts/items/modules and ensure that there is minimal risk of them being unsuitable for my project or design?
I just want to know why the Linear time-invariant(LTI) systems are a rich class in Signal Processing. Ofcourse there are different systems but still LTI is stressed a lot in academia. Is there any ...
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...
If the external power supply to a device fails, and I can't get the exact model, what do I need to specify to get the right replacement? I can re-use the old supply's connector, but what about the...
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...
My question is trying to understand if there is an effect on the switching time, on both turn-on and turn-off, between the following configurations. A mirror set up to switch a current, and there ...
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'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...
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...
