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H: MOSFET started to smoke when switching a 12V bulb - how can I troubleshoot the cause?
This is the case: 12V bench power supply (current limited to 3A) wired to a 30W LED bulb (H7 bulb for vehicles), controlled by an Arduino via the gate of the 2SK1363.
The signal from the Arduino was sent to the gate by a pushbutto... |
H: Are BLDC motors permanent magnet motors also?
I have to buy a BLDC motor and I was expecting it to be a permanent magnet motor and also when I read on internet link
Where it was mentioned that BLDC motor are permanent magnet motor.
But when I contacted the seller if it is a permanent magnet motor or not they said i... |
H: How to fix this VHDL error
I am getting an error in my VHDL code. It says "[Synth 8-27] else clause after check for clock not supported". Why is this?
Below is the code:
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
use work.Data_Sizes_Package.ALL;
entity... |
H: How can a ring oscillator work without burning?
I built this ring oscillator and it works fine. After a while I wondered how can it work without breaking.
I am powering it with 5 volts so at start let's say capacitor is charged with 0 volts and a blue node is at 0V. So capacitor starts to charge via R1. When it rea... |
H: Why would you protect a 120-277 LED driver with a fuse that is 600V rated
Sorry about the silly question but is there a reason why you would want to protect a 120-277V LED driver with a fuse that is 600V rated? Does that really protect the device/driver?
AI: The voltage rating is only a maximum rating for the fusi... |
H: Placeholder capacitor
I've seen in many reference designs capacitors that were referred to as "placeholder" capacitors. what are these capacitors exactly needed for?
for example, in DDR4 SODIMM Design:
AI: Sometimes it is cheaper to draw a place for a capacitor and not mount it, so it can be populated later if nece... |
H: Autodesk EAGLE: PCB layout lost when copying from schematic
On one panel, I'd like to have 4x4 'boards' that are all the same. When I copy the respective 'group' in EAGLE, I am losing the placement of the components with respect to each other in the PCB layout. How can I fix that?
AI: Because each new group you cre... |
H: Why does LM324 Op-amp send out max voltage when I got 0V at the non inverter input?
I have this circuit.
The goal is that it going to control the current loop by using the NPN-transistor. My problem here is that 0V results that the output from the Op-amp is near 24V. Why?
If I'm increasing the voltage a little bit... |
H: Solving nodal analysis equations using matrices- gives a full rank matrix
I am trying to solve for node voltages in a circuit using nodal analysis. I am using the fact that the sum of the currents into each node must equal 0.
I have a system of equations which can be represented in matrix form as [G][V] = [0] where... |
H: Surprise resistors found in old voltage divider
I'm a grad student in physics that hasn't looked at circuits since early in my undergrad. I was recently handed a voltage divider that my group used to bias a micro-channel plate detector stack as I'll need to build a new one for a new system.
What I'm confused about ... |
H: Will diode be turned on?
Assuming we have this circuit:
simulate this circuit – Schematic created using CircuitLab
Assuming D1 is a silicon diode and D3 is a germanium diode,Will D1 be turned on so the VAB = Vfd1 or not?
I know that if we didnt have the resistor D1 would not turn on but now i am unsure.I also kno... |
H: How to feed reference voltage for two op amps inputs with different input signal each one
Im building a Stereo Buffer and a Baxandall circuit together. In powering the circuit with a single supply of 9v, and i need to bias each four inputs with 4.5 volts. The question is: If i feed the four inputs with the same ref... |
H: Phototransistors in parallel
We are trying to hook up phototransistors in parallel so we can sum the output currents and put it over a resistor to get an output voltage.
When we do this, the first phototransistor (closest to the voltage source) seems to be greatly affecting the output voltage, and the others are ne... |
H: Has anybody used STM32F417IG microcontroller with 1.8V input supply?
https://www.st.com/resource/en/datasheet/dm00035129.pdf
Currently, I am using STM32F417IG with a 3.3V supply. If I want to use a microcontroller with a 1.8V supply to avoid level translators in the new design. Is there anything I should consider i... |
H: 6.6kV digital isolator pad clearance
I was wondering about digital isolators. I have some temperature sensors installed inside the windings of a 6.6kV motor. I would like for my system to not be completely destroyed in case of a short.
For instance, the Si86xxT isolators from Silicon Labs. They offer 5kVrms isolati... |
H: AVR Atmel MCUs with 12bit ADC and ArduinoIDE support
I am searching for more powerful MCUs than the ATMEGA1284p that I am currently using, in particular I want to have better ADCs and switch from 10 to 12bit resolution. My constraints are the following:
12bit ADC
Low-power during sleep
Available Arduino bootloader... |
H: Can I operate 2 electromagnetic locks using the same power supply?
I'm using this power supply:
Specs:
Input Voltage: AC90V-AC260V 50-60HZ
Output Voltage: DC12V
Momentary Current: 3A/5A
Persistent Current: 3.5A
To operate my electromagnetic lock situated on the top edge of the door.
Specs:
Holding force: 180kg(3... |
H: Shunt resistor after MOSFET and op amp to amplify voltage
I'm trying to figurate out how to measure current in circuit. I have idea to use shunt resistor but after connecting op amp on shunt I have some unpredicted measurements on output of op amp. I want to measure amps of leds. Is this good idea to measure curren... |
H: Registered signal and Fmax in Timing Analyzer from Quartus II
I have the following module that is a simple register:
module linear_out
(
input clock,
input resetn,
input [31:0] x,
output reg [31:0] y
);
always @(posedge clock)
if (!resetn)
y <= 32'h00000000;
else
... |
H: What happens when the motor torque is constant and the load torque suddenly decreases?
It is a situation where the load torque (Ta) suddenly decreases while rotating the shaft with a motor(PMSM) at a constant motor torque (Tm).
In my opinion, the rotational speed of the shaft (I-moment of inertia) and motor will be... |
H: Current values after power factor correction
I am a student tasked with correcting the power factor of an RC circuit to unity with a parallel inductor...
Vrms = 240V, 50Hz
R = 12ohm
C = 220uF.
I have calculated the inductor value by calculating the reactive power.
I simulated the circuit and the voltage and current... |
H: Understanding driving a relay with a transistor
For an embedded application, I'd like to drive a relay using a transistor. At the moment I'm experimenting with a BC547, but only because I've still got some of them lying around.
The transistor I am using is rated at a max of 100mA continuous for the collector (or co... |
H: Choosing the shunt resistor value and capacitor for op-amp integrator based on input resistance and DC gain
I think it's option C based on C = 1/R and the R2 as 10 times R1 but apparently the answer is option A.
Please tell me where i'm going wrong.
The full question reads
The following figure shows opamp-based i... |
H: PIC18F4550 : How to convert 16 bits integer to two 8 bits chars in C?
I'm blocked because of an issue that is causing a lot of time loss. I've created a function to get the LSB and another one to get the MSB.
char get_LSB (int n){
unsigned char lsb = (unsigned)n & 0xFF; // mask the lower 8 bits
return l... |
H: How to make sure my motor will not start spinning on power up in case the throttle (POT) was not at a 0 position?
I am trying to make sure my motor which is connected to my controller circuit would not just start spinning when you first apply power to it as if the Potentiometer is left high before the battery is co... |
H: use MOSFET as a switch in saturation region
According to this data sheet at 6v GATE voltage , the saturation drain current is about 1.25A. now I want to switch a device (say a tiny motor) which demands 1.25 A at 2volts , Indicating the resistance 1.6 ohms. now I am supplying the drain source voltage 4 volts.(as usu... |
H: Dual Power Supply for single 10m LED Strip Run
This is my first time here so sorry for any wrong formatting.
I am currently creating a project where I will run my wall with 10 meters of addressable LED strip (Made up of 2 x 5 meters rolls). I have two 20 amp, 5 V power supply for the project. After calculating 60 L... |
H: Why do some motors have both 50Hz and 60Hz on their nameplate, and some do not?
I have seen some induction motors have information on their nameplate listed for 50hz and 60hz. While I've read a requirement that the Voltage/Frequency ratio be consistent, using these nameplate numbers you can come up with examples li... |
H: Two stage amplifier, low gain at high frequencies
When I simulate one stage amplifier it is capable of amplifying to a much higher frequency than a two stage amplifier.
I added a 100 ohm resistor to reduce the gain of the two stage amplifier so both the gain curves could fit in one graph, but you get my point. The ... |
H: Build a circuit to modify a printer's power supply
Can I in anyway build a simple circuit that would change the printers power supply to be able to power the printer in the photo?
I want to convert a 22V 455mA power supply output to 16V 500mA output to power the printer. How can I do it, and what components will I ... |
H: minimum C rate of battery cells
What is the minimum C rating for li-ion battery cells? I am trying to charge 3.7V 10Ah battery pack with small 0.3W solar cell. I used LTC3105 DC/DC boost converter to boost voltage of solar cell to 4.2V. I could not find any online documentation or thread for this. I know it is safe... |
H: What to do with the /RST pin?
I'm using this gate driver IC. My question is, do I have to externally pull up the /RST pin? Because it can't be left floating, but I don't get the part that says "pulled down internally".
In the datasheet this is mentioned,
So is this correct to be connected like this?
AI: Pulled dow... |
H: Push button with auto off
How to make push button switch with auto off after about 5 seconds.
Output circuit is high (active) for max 5 seconds when I keep pressing push button.
Output will be low after this time or when I release push button.
To reactivate, I have to release push button and press again.
I think t... |
H: Transformer Harmonics
A typical installation is
Load - 400 V net - Transformer 1:25 - 10 kV net
If the load is for example a SPS, the 400 V net can contain harmonic currents and thus have a considerable THDi.
How can the transmission of harmonics or disturbance from 400 V net via Transformer til 10 kV net be descri... |
H: I would like to know what this circuit is
I'm a engineer of embedded systems and I'm studying a 4G modem. The circuit has a component that I want to identify but the reference is apparently wrong. The reference printed in the circuit is H51RFA but I couldn't find this in any place. You can see a picture below.
AI:... |
H: How to calculate how much current is available from Buck regulated Solar Panel
I'm trying to work out how much current my solar circuit could sustain under normal conditions.
I have an monocrystalline solar panel claiming 5W @ 12V (17.8V Vmp, 5Wp) based on their data sheet.
The data gathered by CEDA from MIDAS near... |
H: Using and maintaining lower end soldering iron tips without destroying them
I bought a low end soldering iron of eBay - it was advertised as a "15 in 1 Soldering Iron Kit", and was advertised as temperature adjustable. It has a dial to adjust the temperature with numbers in degrees Celsius.
I put a new chisel tip f... |
H: Are there 2D-Transformers?
I need to create a PCB with a transformer on it, and in this case, I unfortunately can't solder on a regular one. I was wondering if there was anything akin to a 2d transformer, or just generally a coil I could print onto my PCB. I know that spirals are used in Radio-Applications, but I'm... |
H: How to change adc sampling time in STM32 to 20 Hz
I want to change the sampling rate of my STM32F303RE to 20 Hz. Is this possible with a ADC clock with 8 MHz and without a HAL_Delay() function?
AI: Use a timer to trigger the ADC. Then you can vary the sample time to your heart's content.
You really don't want to pl... |
H: WAVGAT Arduino Pro mini I2C pins?
I'm trying to hook up an OLED display using I2C communication to my Arduino Pro Mini clone(with ATmega 168, 16MHz) from WAVGAT but I can't figure out where the I2C pins are on the Arduino.
AI: The "official" Arduino Pro Mini pinout is:
So your I2C pins SHOULD BE at the A4 and A5 p... |
H: DRL AND gate circuit design
I have a guide stating that the following diagram represents a DRL AND gate:
Suppose that both A and B have 5-V inputs with a corresponding switch. I tried to simulate it for learning purposes and placed the ammeter right before the LED. The problem is that the current does not change a... |
H: High potential between ground and neutral wires in wall outlet
I would like to test if ground connection works properly in my wall outlet. To do so, I have tried to measure voltage across ground and neutral wires. And here comes the interesting part:
U(Live, Neutral) = 198V (220 +/- 10% V AC, fine)
U(Neutral, Groun... |
H: Why is there a negative voltage?
Can anyone explain why do we have that negative voltage VEE?
I know that it's a DC voltage, from its name, but I can't find the explanation for why is it negative. Also, Vi1 and Vi2, from that symbol I know they are DC but shouldn't we have AC as well?
AI: In this case the "negativ... |
H: Settling time of sixth order denominator transfer function
I have a system whose transfer function is as follows
$$
\frac{V_o(s)}{V_i(s)}=\frac {\text{numerator}(s)}{a_1 s^6 + a_2 s^5 + a_3 s^4 + a_4 s^3 + a_5 s^2 +a_6 s + a_7}.
$$
I am interested in the settling time exhibited by the system, hence the numerator is... |
H: MOSFET power supply ON with no MCU input
I have a MOSFET circuit that a microcontroller manipulates (using its GPIOs) to control power to other devices. I noticed yesterday when I detached the microcontroller from the circuit the LED on the board was still lit up. So this means that 5V on the MOSFET's supply was ... |
H: How does current flow in this circuit
I'm just trying to visualize how the current flows in the following circuit. It is a follow-on question from here. The circuit is a small-signal model for a common-source MOSFET with source degeneration. In particular it is analysing the output resistance using voltage source V... |
H: Output impedance of a voltage divider with DC bias
I made a circuit simulation of a 200VAC to 0-2VDC for ADC conversion via voltage divider and DC bias with a third resistor connected to a 3.3V supply. What is the output impedance of the divider and how do I calculate it?
AI: The output impedance is not affected by... |
H: Is there a way I can convert from USB to LVDS UART (~1Mbps)?
I'm working on a spacecraft that requires very low noise levels so it was requested that we pursue LVDS UART. So it's using something similar to RS-422 because it's differential, but instead of a signal that is 0-5V, it is a current loop that produces a d... |
H: How does a Touchstone (s2p) file indicate whether it should pass or block DC?
I'm trying to simulate impedance matches for an LDMOS FET amplifier with Touchstone (s2p) files to simulate the device with "real components" before we build it. I have found that "capacitor" s2p files leak DC current and that "inductor"... |
H: Anyone have any idea what type of receiver/transmitter that is
I got those from someone and it does not come with any kind of datasheets
I’m guessing they are receiver and transmitter as they both have kind of an antenna.. anyone have an idea of the model so I could google the datasheets
Thanks!
AI: That's a "GWB T... |
H: VHDL synthesize std_logic 'H'
Can the weak-pullup 'H' assignment of std_logic be synthesized, or is it only allowed in simulation? You're probably wondering why I would want to do this: I'm trying to emulate both the master and slave I2C devices inside the same FPGA (internal bi-directional bus), thus I have no ext... |
H: Troubleshooting DTL NOT gate circuit design
My guide says that the following diagram is a DTL NOT gate. Its output is a LED.
For learning purposes, I tested it via a simulator. The measured current is not really significant to power on the LED. Opening and closing the switch does not bring enough difference to pe... |
H: Do we always take the corner frequency of a filter at exactly -3dB?
I'm doing some work on filters, but all the references I can find use a 'perfect' gain characteristic, with the trace starting at 0dB. Is the measurement for corner/cutoff frequency always taken at exactly -3dB? What if the maximum gain isn’t 0dB?
... |
H: Total resistance across a capacitor in series
Why is the total resistance across the capacitor \$R_{\text{sig}} + R_{\text{G}}\$? Why is it not just \$R_{\text{G}}\$?
AI: Part of the issue is that you asked for the resistance measured across the capacitor without actually understanding what that means.
It means as... |
H: Circuit to detect in which port sensor inserted
I want to build a Counter using a Proximity Sensor. I want to give choice for user to use either PNP or NPN. I will give two ports for the same. I am using PIC16f887 microcontroller.
How to detect that which sensor user inserted?
I dont want to miss any sample just t... |
H: Why can't KVL be applied here?
I was asked to find the Is current
I applied KVL in that loop but my ans is wrong.
what concept is wrong on my approach?Why kvl cant be applied on that loop please explain
AI: Because the current through \$ 1\Omega\$ is not \$2-I_s\$ as you have assumed. It is actually = \$2-(I_s+I_{... |
H: What was the communication protocol used on board the Apollo moon lander?
It seems that the development of TTL was contemporary ~1961 the maiden moon landing of the Apollo vehicle, while the development of one of the oldest digital signalling standards RS232 using the UART hardware was crystallized later, and that ... |
H: Do switches induce voltage spikes in the AC power grid?
I know that DC inductive loads create back EMF when turned off and that's why we use a freewheeling diode.
Does this also true for AC inductive loads and AC loads in general?
I know we can't use a diode though.
I've noticed when I turn on and off switches arou... |
H: Voltage multiplier circuit not working
I am trying to make a voltage multiplier circuit. When I connect it to mains \$120 \; V\$, the output voltage becomes \$90 \;V \;DC\$, I do not know why this is.
Capacitors: \$20 kV \; 1000 \; pF\$
Diodes: \$4 \; 12\;kV \;5\;mA\$ and \$2\; 12\;kV\; 350\;mA\$
Edit forgot t... |
H: High current bus bars on PCB controlled with mosfet and Raspberry Pi
I need to be able to switch up to 100 amp @ 48v DC with a Raspberry Pi.
I came across this video which is what I am trying to emulate:
https://www.youtube.com/watch?v=dhIbZa6yg5k
at 1:15 in the video it shows how they have the mosfet connected to ... |
H: How to select LEDs for use as colour selective photodiodes?
When selecting LEDs for use as photodiodes, are there general guidelines that one can use to increase the odds that a more suitable LED is selected?
For example:
Does diffuse or clear impact efficiency as a photodiode?
Does a brighter or dimmer LED tend t... |
H: How is the output voltage adjusted on this schematic?
This is a schematic of TI's reference design for a 65-W USB Type-C high density active clamp flyback with GaN (PMP21639), which can be found from this reference design page.
The page claims that the design has a maximum power rating of 65W at 20V output, but is ... |
H: How to get the unknown variables through voltage division?
Given this circuit, how do I find E, Vz, and Vy when Vx is 3V?
When I tried solving it, through simplification of circuits, (correct me if I'm wrong) I got a total resistance of 12k while resistance of Vy is 10k. Upon getting the total resistance, I used th... |
H: How is the intensity of sensor noise determined experimentally?
Consider a sensor for which we are designing a Kalman filter for improved accuracy or sensor fusion. Let us restrict this discussion to the goal using the filter to improve the accuracy of the aposteriori state estimate and avoid addressing sensor fusi... |
H: What is the transparent border around my Altium trace?
I am routing my first ever PCB and half way through the routing process I've noticed my tracks now have this transparent border around it. Any idea what this is ? I must have clicked something? Not sure how to disable it nor what it actually represents.
AI: Tha... |
H: STM32 ADC read methods for high voltages
I want to read input voltage from a solar array for my circuit. That's not a big deal if the voltage is up to 3.6V. The problem is that I am expecting maximum of 15V and obviously I won't be able to have connection for ADC reading.
First solution that came to my mind is crea... |
H: Altium: Component Clearance constraint won't go away after setting rule
I am using Altium 18. I ran a DRC check and got the following error:
This is saying i don't have clearance between J2 and MH2. This can be seen in the PCB:
However, i have set the following rule:
Surely this should get rid of this error? Wha... |
H: How to stop ESP32 resetting when motor starts?
This is my first post here and I'm new to electronics. I am trying to control a motor using an ESP32 Cam. See attached image for a rather crude schematic. The power supply is rated for 2.4A. I am using a 12v DC 5rpm worm gear motor like this DC 12V Worm Gear Motor .
Wh... |
H: What could be generating this waveform in an EMC Compliance test?
We are having trouble with a CISPR-11 (EN55011) Radiated Emissions Class B compliance test in one of our solutions. The troubling part of it is basically an industrial motherboard (with a commercial SSD and commercial RAM) within a well grounded meta... |
H: Dotstar Light Strip Low Update Frequency
I've built the start of a persistence of vision display. The rotation platform itself is built and I have just mounted the LEDs. After doing some testing, I can only get very slow update speeds of the lights themselves. I am using a very simple for loop in Python3 on a Raspb... |
H: How does reading from a peripheral device at a specific address using SPI work?
This question is about trying to understand how the communication is implemented on a typical peripheral device such as an accelerometer, or flash chip.
More specifically, I'd like to understand how a peripheral device is able to start ... |
H: Solving for electromotive force constant in motor armature circuit
I have a motor with the following parameters. The motor has gear ratio of 19:1 all values are shown at 12V.
According to the electric circuit of the motor armature, this holds:
Circuit:
how to solve for the k_e constant? I tried to solve for R_a ... |
H: Why does Moore Finite State Machine need more states than Mealy Finite State Machine?
I was reading about finite state machines. I read about Moore and Mealy machine and also the state representation. I read that in the Moore machine the output depends on the present state only and in the Mealy machine the output d... |
H: What are the 9V battery terminal size specifications?
I'm trying to find the dimensions of a 9V (PP3?) battery (no specific chemistry). For some reason it's giving me a lot of trouble. I've been able to find most of the information (I checked a bunch of sources and they've all got these same values):
However, I ca... |
H: Which USB spec actually defines support for Dual Role Device? Type-C or USB 3.1?
I'm trying to get a concrete answer on what determines DRD support... the port type (USB-C) or the protocol type (USB 3.1). Besides the poor naming scheme with USB 3.0/3.1/3.2, there's a lot of lacking communication about the DRD devi... |
H: Voltage across open in this diode circuit with two batteries
Trying to understand how voltage \$ V_{D1} \$ is found.
Here's the original circuit with solution:
Here's how I think it can be redrawn, basically the grounds are just one node:
So to find voltage \$ V_{d1} \$ one first considers what's voltage at point... |
H: What is a ‘dense integrated circuit’ or ‘integrated function’ and how does it relates to Area in Moore’s law?
I am very comfortable with the usage of the Moore's law and its impact on microelectronics. However I had always associated Moore's law to the gate length scaling as a factor of square root of 2 every two y... |
H: Atmega2560 AVCC decoupling
We have designed a custom prototype board based on the Arduino Mega (ATmega2560).
Our knowledge on electronics are limited so we assigned someone else to design the board.
On his design he used the following circuit for noise filtering and decoupling the Voltage on the AVCC and AREF pins ... |
H: SMPS (LM2678) what transformer to use and why?
I have made a few power supplies in the last year (only linear ones using voltage regulators). I have always used a big simple step down transformer, from 230v down to 12/24v (depends on the supply i need).
There are a lot of circuits out there on how to make the power... |
H: Why do we use closed-loop feedback in buck converters?
My power electronics professor spent most of his life in the time domain and in application-specific theory (SMPS-only vocabulary).
For me, a buck converter is basically a square wave (generated by a switch) passed through an LC filter.
The square wave's fundam... |
H: How to transmit data over a long distance at a affordable price
Please do keep in mind that I have no background in electronic communication. The idea is to receive data from electronics at long distances.
The distance I will be looking at to read data from electronics is around 10 km (6 miles) and possibly at a l... |
H: 7405 TTL Chip outputting nothing when given low input
I’m struggling learning how to use some of these components for a lab. One thing I noticed is that when giving the 7405 hex inverter a low input, the output when checked by my logic probe shows there’s no voltage coming to the output. I’ve ensured my chip is pow... |
H: How can I make contact with the material if soldering is not possible?
Sorry for the title, I have problems putting it to words in English.
I ordered some small and cheap Chinese solar panels. I thought it was fun to tinker with them and learn about electricity. After my horrible soldering I found out I want them i... |
H: Can I ground a digital pin on an Arduino to provide input?
I want to monitor whether a fan is turned on or off. No RPM, no voltage levels... simply just is it on or off. The fan is 12V and is controlled by a relay. The relay is closed when a thermocoupler reaches a certain temperature and grounds the internal co... |
H: TTL to RS232 logic translation
Preface: I don't have any MAX232 ICs handy, and only need unidirectional communication (from TTL to RS232). It's just a quick test to see if an old GPS OEM board still works. I don't have any MOSFETs on hand either - just some basic BJTs, as shown in the schematic. I'm using a dual su... |
H: How to wire this transformer? I am not clear on what these wire colors mean and where they go
I read several color coding guides but I am not sure which wire goes where... My guess is that the black is the L wire, which stands for Live, and the white wire is the N, which stands for Neutral, and that I should ignore... |
H: Arduino Uno microcontroller pin broke off
The lowest left pin in my arduino uno microcontroller (ATMega328p) broke off. That would be pin PB0 (pin 14). I am wondering, would this have any effect on the microcontroller's functionality, or can I continue to use it if I just ignore this broken pin?
Thanks.
AI: The fun... |
H: 50Ω Impedance Matching with Signals Through Vias
I'm working on an IoT board and it is all laid out (LTE, GPS, BLE, WIFI - 30mm x 30mm -- VERY TIGHT).
As a design concession, I have to use vias to route some of the RF signals. There's no other way to keep the board that small.
I've impedance matched and tuned seve... |
H: Control color of Bi-Color LED using Arduino
I have this push-button switch which has two solder lugs for 12 VDC power and will illuminate red or green depending on the polarity of the wiring. It may not actually use a bi-color LED, but it seems to be a good representation for how it works. I can't find a schematic ... |
H: Op amplifier ad8232
Does anybody know how this op amp is working? And what the output signal is - avL, avR or avF. I don.t find similarities compared to a real ecg.
**** Edit
I don.t understand how this amplifier returns this particular waveform if we connect those 3 electrodes.
Does single-lead means that it reco... |
H: Do stator windings on a permanent-magnet synchronous three-phase ac motor have sinusoidal distributions?
In motor-drives textbooks (e.g Ned Mohan's Electric Motor Drives), the text states that the stator windings on ac machines (e.g. PMAC three-phase motors and induction machines) are, in theory, sinusoidally distr... |
H: Whats wrong with this design
I was looking at what goes into driving an LED strip from a microcontroller and i found this
https://electronics.stackexchange.com/a/67780/41661
which has this schematic
In the question the op states the PWM 3.3v is coming from a MCU but he never states what kind of MCU he is using.
I ... |
H: 3.3V interface on arduino is only giving 0.23V
I just received an Arduino ATmega2560 (GEEKCREIT).
The 5V interface is giving exactly 5V as expected.
But on the 3.3V interface I could only measure 0.23V.
What could be wrong?
AI: The first thing to verify is the 3v3 regulator, you could start measuring voltages at t... |
H: Derivation of ripple factor equation for a full-wave rectifier with filter
I'm trying to derive the ripple factor for a full wave rectifier with a filter.
This parameter is defined as the ratio of the root mean square (rms) value of the ripple voltage (Vr_rms) to the absolute value of the DC component of the output... |
H: 4n25/35 optocoupler detect led on/off
Hey all i am just wondering if my drawing below is correct in order to have an arduino detect an on or off led on another board using a optocoupler?
My thoughts of the above drawing is that when the led is on it will trigger the relay inside and send 5v to the arduino digital ... |
H: Are present state and next state equal between two clocks?
I know things that happen every time clock ticks. Present state and inputs are delivered to the combinational circuits and it produces the outputs and the next state information and sends the next state to the memory elements. Then memory elements(e.g A SR ... |
H: Superposition problem with \$\Delta\$-Y conversion
I'm trying to use superposition to solve the following linear circuit:
Step I step I considered each active component as:
But results are always wrong.
Same procedure on many other circuits give me right answers, but not this one, for some obscure reason.
For ... |
H: Rogowski coil response factor frequency dependence
I am creating a high current (kA) pulse (<1 ms) by discharging a supercapacitor into a low resistance (<1mOhm) circuit. The switching is done by paralleled power-MOSFETs.
To measure the current I use a rogowski coil (RCT16-50000 from Accuenergy, no data sheet provi... |
H: Relay output from MCU with enhanced safety level
I want to do a relays output with enhanced safety level (redundancy and EDM).
For that, I plan to use two force-guided relays driven each by N-channel MOSFETs.
However, I'm wondering if I can use only one MCU outputs to drive these two MOSFETs or if I should use one ... |
H: Won't get 5v on input of Arduino with power bank
I don't know why but i'm not getting 5v on the input of the Arduino, the only thing I've done is to add a switch in order to interrupt the circuit. Here it's my schematic:
I have another issue with the battery charger, I don't know why but in order to output tension... |
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