text stringlengths 83 79.5k |
|---|
H: Microcontroller and decoupling capacitors on the VDD layer
I have a microcontroller design that is implemented using a two layer PCB. All the components need to be placed on the bottom layer due to the fact that there is a display in the top layer.
In short, I ended up placing all the components in the same layer a... |
H: What does "bolt-on" mean in this Arrow Electronics' job posting?
I came across of Arrow Electronics job posting, and wondering what term "bolt-on" means. While I can find generic description of this term, I can not understand how it relates to the electronics and duties of the job holder. I found subsection "bolt-o... |
H: Where is the positive and negative on an antenna?
What I am wondering is how to build an antenna. Upon unscrewing my telescopic antenna from it's base, I see only a metal screw base, nothing more. The F Connector has a positive and negative (or ground) connector, the outside is negative and the pin in the center is... |
H: Altium not starting!
So I use Altium for designing and on most days a quick restart generally makes things normal. But today Altium refused to start at all.
I could see in task manager multiple instances of Altium though all were frozen.
Any way to get the Altium to run or do I need to uninstall and install the w... |
H: 3.3V step up to 5V using BJT
I'm using an Arduino Blend Micro with outputs that provide only 3.3V and I need to control a MOSFET that needs 5V on its gate. Can I step up the voltage from 3.3V to 5V using a single BJT?
AI: The current in my coil is about 20A with 16V. The speed is not really
important, it's only t... |
H: Is it acceptable to use 1uF decoupler on a 7805?
I am feeding an arduino, presently through its Vin pin, with a 0.9V drop on its onboard regulatorZ I'd of course like to feed it via its 5V pin, which has a strict upper limit of 5.5V. I don't have any 7806/7808s, and already soldered the 7805 in place. I also have n... |
H: Spark Gap in EMP Generator
I recently got into eletronics, and there are some concepts I am having a hard time understanding. I was looking around youtube and saw this video of a small EMP generator, I understand the basics of it, the magnetic field inducts a current thus frying electronics, but what I'm interested... |
H: A confusion about a transfer function's Bode plot and s domain view
Recently I have been stuck with a simple Bode plot and H(s) comparison.
To begin with, here is the transfer function:
H(s) = 1/s
For Bode plots I write:
H(jw) = (jω)^-1 = 1/(jω)
For the magnitude and phase I use:
|H(jω)| = 20*log(abs(H)) versus log... |
H: Using Tim2 (84MHz) to blink Led for every 500ms - STM32F407VG
I developped a code in ordrer to blink a Led every 500ms using the timer 2 with a frequency of 84Mhz.
I generate the file "system_stm32f4xx.c" to have a frequency of 84MHz for Tim2.
I modified the file "stm32f4xx.h" by adding the line
#define HSE_VALU... |
H: How do you prevent a speaker from interfering with an array of buttons that use a voltage ladder?
Short story
I have a PCB with 3 buttons on it, each button connected in series with a different value resistor forming a voltage ladder (schematic below). On the same PCB, I also have connected a speaker. The negative ... |
H: Selecting a cable for 12V and 24V off-grid solar system
I have two systems connected to 1500W power inverter. Per case as shown below, what size (4mm, 5mm, 6mm ....) cable should I buy?
Note: Based on my researches, the smaller ah output the thinner cable thus the system becomes more reliable, safer and cheaper etc... |
H: PCB Mount Relay Causing Reset
Working on existing PCB which has reset issues. Have been able to solve all reset problems except the following:
Using a PCB mount T9AS1D22-24, upon micro going low on Q3 base (K3-A coil de-energize), micro will occasionally reset.
Have attached circuit for viewing. Anyone have suggest... |
H: Neutral and the earth are bonded at the main panel or the substation but why is only earth wire used for safety?
Typical distribution system can be illustrated as:
Here are my premises (and assumptions):
1-) Chassis in a house must be connected to the earth, not to the neutral.
2-) The earth and the neutral are co... |
H: Emitter follower/Common collector confusion
I'm in the need of a buffering circuit for a project and I would like to use a common collector amplifier or emitter follower for this purpose. Above is a schematics of the circuit I'm looking into.
However, I'm having slight trouble understanding this circuit, specifica... |
H: 3 Phase Dyn5 transformer neutral groundig
What happens when a Dyn transformer grounding fails? The transformer has mixed loads (1phase, 3phase) also unbalanced. It is going to act as an isolation transformer or ...? Will the phase and line voltages remain the same?
AI: If the ground connection opens in a grounded n... |
H: Additional resistor in feedback loop of bridge audio amplifier
Here is the bridge configuration of the TDA7294 audio amplifier, from its datasheet:
Everything is clear, despite the 22 kOhm resistor connected between output of "top" amp (pin 14) and inverting input (pin 2) of "bottom" amp. Could someone explain wha... |
H: decreasing the range of an lnfrared emitter
this is probably a weird question that has never been asked... but I was wondering how/if it is even possible to decrease the range of a infrared emitter?
here is why I need to know:
I am playing around with making laser tag weapons and I was working on a shotgun. how I h... |
H: Tuning BJT avalanche noise
I'm playing with the idea of building an audio noise maker. I found several nice sources. Most seem to be based on PN junction avalanche noise. As a starting point, I put this on a breadboard:
It works, but I'm not sure I understand it completely.
Q1 generates the noise and Q2 amplifies... |
H: How can I interface a Raspberry PI GPIO to an open collector circuit to send / receive data?
I have a GPIO from a Raspberry PI connected to a Nintendo 64 system like so:
From what I've gathered and observed, the data line on the N64 system is an open-collector output. The line is tied high when data is not being t... |
H: Replacing a PC's AC-DC converter with a DC-DC converter for mobile power supply
I'm going to be purchasing a mini PC to act as a mobile work station in a set of field experiments. The field locations do not provide power, so I'm trying to come up with a mobile power supply.
For starters, the mini PC utilizes an AC-... |
H: Building a (toy) Ghost Detector
I'd like to build a ghost detector. I'm only just beginning the design stage, and thought I'd reach out for some suggestions.
Receiver: I'm planning to end up with a handheld device with an analog backlit meter, which illuminates when the house lights turn off. The meter will display... |
H: Capacitive Voltage Divider and Discrepency in Output Signal
Background
I designed a capacitor voltage divider for the purpose of measuring the voltage step up of a resonator. Before I measure the voltage step up I wanted to measure the voltage divider ratio to ensure it matches the theory.
My Circuit and Theory Res... |
H: Math Regarding Battery Discharge
Good Day everyone :)
I'm new to electronics and it'll be my 2 week practicing it as my hobby though i've done a lot of DIYs and stuffs just by following tutorials but when my friend ask me regarding the maths of my projects, i can't retaliate at all since even i researched for 2 day... |
H: How to convert a device pluggable to a car lighter, changing to a regular home socket
I bought an air compressor that is powered by the car lighter in my car. It does the job when I want to inflate my car tires, but if I want to use for something else like there are 3 bikes in our house and they all have to be regu... |
H: Is it a good PCB design practise to choose components with the same footprint?
Most of the components I have selected for my project have 2012(mm) footprint while some others have 1608, 3225 and 6432. Does it matter that some components have a different footprint? What is a good design practise?
AI: Generally you w... |
H: DC-DC converter bypass for VIN = VOUT question
I need to develop a device that requires 5V power. The device must be powered from 5V (USB) or 12V. I need such a system that will bypass the DC-DC converter when it works from USB and enable the DC-DC converter when it works from 12V.
Will my solution work?
I want to ... |
H: Friction Coefficient of AC motor
Does the Friction Coefficient "B" of AC Motor changes with the change of a load connected to an AC motor? OR it is always constant?
AI: The coefficient of friction is the ratio of the force of friction between two bodies and the force pressing them together. The only friction in mos... |
H: Antenna Matching Network
I am trying to match a gsm antena, doing it on a pcb, first time in practice. I understand the whole process to adapt it, I've done it in simulators. However, I don't understand the need for a pi matching network, since (theoretically) and LC circuit is enough, or a series and shunt capacit... |
H: stm32f103c8t6 help
I bought a STM32F103C8T6 evaluation board (which I have not received yet).
See link
But I'm a bit lost in how to start with it.
I have some experience with Arduino Uno/Mega.
I found already that the Arduino IDE supports them, so that's a good starting point.
However, even before seeing one, I hav... |
H: What is this waxy stuff?
I just opened up an old piece of electronics. While salvaging, I found a board with this waxy stuff on it? What is this and what is its use?
P.S. The substance I am talking about is the lightly tanned wax on the top right of the board.
AI: Am guessing that the wax-covered part of the circu... |
H: Static error in analog-to-digital conversion
I'm testing ADC and quantization noise on a microcontroller (dsPIC33EP64GS506), but I've realized that I have a static error in a digital signal.
I measure a DC voltage on a voltage divider and my multimeter measures \$2.267~\text{V}\$, while the analog voltage reference... |
H: Is the optocoupler placed before or after the gate driver?
Is it
MCU - OPTOCOUPLER - GATE DRIVER - MOSFET
or
MCU - GATE DRIVER - OPTOCOUPLER
and why?
EDIT : it cannot provide enough power so it is used for signals therefore option 1.
AI: Option 1 is correct. The purpose of opto coupler is to electrically iso... |
H: Minimum Switching Frequencies in Boost Converters
Why are switching frequencies for boost converters above the 100kHz range?
If I understand correctly, as the frequency increases from 100kHz upwards, the ripple current that is created from the inductor decreases, the current change over time decreases in the induc... |
H: Why is the input noise of an op-amp often lower than the Johnson noise equivalent to its input impedance?
As an example, the OPA227 has 3.5nV/sqrt(Hz) input voltage noise density (at 10Hz). Its input impedance is 10MΩ, which has an equivalent Johnson noise of 1μV/sqrt(Hz) at room temperature - much larger than what... |
H: How to allow thread and interrupt safe writing of incoming USART data on FreeRTOS?
I have a [circular] buffer that is written with incoming data from the USART using IRQ. I also have other tasks reading data from the buffer as well. What should I do in a scenario where a task has the mutex for the buffer but IRQ ... |
H: Protection from fully charged battery
I want to connect a Li-Ion battery on a GSM/GPRS module expecially this one (http://www.electrodragon.com/w/GSM_GPRS_A6_Module). In general parameters is mentioned operating voltage from 3.3V to 4.2V
A simple Li-Ion battery when is fully charged goes up to 4.2V, somethings slig... |
H: Why can't you just average ADC samples to get more resolution from an ADC?
I'm trying to get more than 10 bits of precision from my Arduino ADC but I can't really figure out the theory behind it. An often quoted Atmel Application note (http://www.atmel.com/Images/doc8003.pdf) says that
It is important to remember ... |
H: Inconsistent solder mask on vias
When looking at PCBs in consumer products or PCBs I have ordered from manufacturers myself, I notice that, while many of the vias are covered in soldermask, it seems like a few random vias are missing it for no apparent reason. This is true even if I specify soldermask to cover all... |
H: USB Audio Input Jitter (?)
Hopefully this is the right sub to ask this question. Anyways, I'm working on a USB Audio device on a microcontroller and I'm having issues with getting a consistent audio input.
Some preface:
As of right now, I have connected the mcu and codec via I2S (codec is slave) with the following... |
H: Guitar to RCA video. Is it possible?
I've recently been playing around with analog video like composite to S-video and VCR related things like that. I've always thought it would be really cool to create some kind of analog video generator from sound.
If anyone could explain how composite video signals work and sho... |
H: How does this power inverter circuit work?
I'm looking for a power inverter for a DC voltage and I found this circuit on Wikipedia (I'm asking about the one on the bottom; ignore the one on top because it's the electromechanical equivalent of the one below.). I don't understand how it could possibly work, though. I... |
H: Why is the PCB so large on this SMPS?
In a post regarding heat dissipation in a linear regulator, one answer provided this nice little pin-equivalent smps. It was a great reply, and I'll likely order a few myself.
I am wondering though, why is there so much empty space? It doesn't appear to need extra layers - exc... |
H: Do buck converters/voltage regulators change max amperage?
I'm interested in dc-dc buck converters and voltage regulators. I want to know if the maximum amperage changes when you adjust voltage or if amperage is affected at all when changing voltage.
Thanks
AI: There are several different things that can limit the ... |
H: Theoretical max rate of input capture for a USB mouse and possible hardware limitations
I apologize in advance if this is not the correct forum for this question or if the question is too broad to answer. My background is in computer science and I work mostly in Java middleware so this is a bit out of my area of e... |
H: What determines if a particular DAC is "good" for audio?
I want to generate low-end audio (sinewave, sampling rate 8kHz). How to determine if a particular DAC is okay for such application? Is it only the settling time (of course apart from resolution, interface, voltage etc.)?
For example the AD5601 has a maximum s... |
H: Resistor ladder network component name
Very basic question I'm sure
I am trying to buy components for a project I am doing, but I cant get the name of a component right yet.
But it has to exist somewhere.
I want a resistor array but instead of the resistors in parallel I want them in series with a point to take a m... |
H: Buck Converter for 59V to 58V?
Some batteries last twice as long if they are kept to 80 percent of their maximum charge. It's good to add a small adjustment to undervolt a charger output by 0.5 - 1V. Myself i have a CC/CV charger that is .5 volts too high for a given BMS.
How can I take the voltage down by .5 - 1V ... |
H: Importance of Body Transconductance MOSFET
I am currently studying about small signal models of Common Drain & Common Gate configuration, where the body transconductance has significant effect on voltage gain and output resistance (when body effect is significant).
I also know the principle of body effect - body ef... |
H: How can I add to LTSpice the MC34063 model?
I found the MC34063 moden in the eevblog forum: link
How can I add it to the LTSpice to if I want to make a buck or boost converter it appears in for.example in the power product list?
AI: Copy the .asy file to the location where the LTspice symbol files are kept, I.e., C... |
H: Increase instead of dip in voltage in a AC to DC Motor Circuit
I have a very simple circuit. 120 AC into a rectifier output to a 120 DC motor. No caps or resisters. Literally a rectifier a DC motor with a thermal protected. No more no less.
When I power on the voltage at the outlet goes to 165 and stays there unti... |
H: How to make a circuit to detect a cut cable properly
I want to make my own alarm system, I put a long cable from my alarm and a sensor, if the sensor's cable is cut, the circuit change it's logic state, and then I read it. But the problem is that the long cable has it's own resistance and other problem I have is t... |
H: Model of capacitor at breakdown
I have looked through the web and couldn't find a model of a capacitor at the moment of breakdown.
After a circuit that I built failed, I took a few capacitors to test and found out that some of them breakdown before they reach the rated breakdown voltage. I
also found out that the c... |
H: Sensitivity list rule in HDL
I have a little confusion about sensitivity list rule: all signals that are read in the always block must be included in the list. When including the posedge CLK and EN in my sensitivity list, I get value of x changed when either of signals in the sensitivity list changes. Thus, if EN c... |
H: Driving a MOSFET with fastest rise time possible
I'm working a circuit to send very short pulses to a load, with the requirement that the pulses have the fastest rise time possible (~10ns or less).
I've picked out a driver that has a fast rise time, the UCC27524P (http://www.ti.com/lit/ds/symlink/ucc27525.pdf).
I h... |
H: How to get 3.3V output from Vishay 6n137 high speed Opto Coupler?
I am using 6n137 opto-coupler to drop down 5v pulses to 3.3v level pulses. I found in data sheet the minimum input voltage is 4.5V at Vcc. and the circuit given in the data sheet has pulled up Vo to Vcc using RL resister. Is it ok if i supply Vcc wit... |
H: How can I calbrate my power meter?
I used to work for a company that made power meters but only worked on the desktop application (user interface) side of things and never really learned completely how some processes occur, like the calibration process. So in order to learn something that I've always been curious a... |
H: Can I run a 12v fan off of a 9v power supply for LED lights and are there any side effects
I have multiple (9v 1500mA to 9v 3500mA) LED light fixtures that I have tested chaining a single fan (12v 5.2w and 12v 0.16A fans) and they seem to work under the brief test with enough air flow for my needs.
Anything I shou... |
H: Power Dissipation VS Switching Power
It amazed me recently to have found 3 tiny Sot-232 transistors inside a 12V led controller. It can't be serious, but after digging and testing it with my 10 watts power LED mounted on a CPU heatsink for 30 minutes, the huge heatsink was hot to touch, yet when stupidly touching t... |
H: How should I interpret the analog switch states of the ADG788?
After reading the datasheet, this is how I interpret the switch states of the ADG788 analog switch:
This interpretation is based on the "Truth table" in the datasheet:
Nevertheless, it feels a bit counter-intuitive. It is weird that the B-poles are co... |
H: Designing footprint for LFCSP CP-8-13 what should be the pad size
I am scratching my head to create a footprint for ADA4817 which comes in LFCSP CP-8-13 package. I reckon this package is only used by Analog Devices.
The main problem is I do not know what should be the pad size for the pins. The pins are stated to ... |
H: What is the bypass capacitor at the emitter of a common-emitter amplifier for?
Why do we have the by pass capacitor parallel to R(E) in this amplifier circuit? They say it is to bypasses the RE resistor for AC signals but then why is it required to by pass the R(E)
They say that it is to avoid the negative feedbac... |
H: Logic Simplification using boolean laws problem
I am new to this, I am stuck on simplifying this logic equation. Any help would be great, thank you.
The equation is:
$$
Y = \bar{A}\bar{B}\bar{D} + ABD + \bar{A}\bar{C}\bar{D} + ACD + BCD
$$
AI: Y = ~A~B~D + ABD + ~A~C~D + ACD + BCD
Let's see what the Karnaugh... |
H: how layout high speed pulse PCB traces?
I am working on a PCB design layout, 3 PCB traces, 350kHz pulse signals (logic 3.3V and 0V) are to send via PCB traces. are there any design rules for this type of signaling through PCB traces?
AI: @peufeu traces into 6n137 opto-coupler and traces from output of it to the fp... |
H: Can I order PCB/chip manufacture from provided LOTOS specification?
Is there a way to automatically deduct PCB and/or chip design from formal problem specification of a problem (task) which supposed to be solved on a PCB/chip?
I'm currently implementing solution with OpenCL to be run on GPGPU in conjunction with CP... |
H: Realizing a multitasking program with Timer Interrupts
This is my attempt to realise multitasking (well almost) through interrupts. In this example, Task 1 is: Toggle LED connected to PB1 at 2Hz (Timer 1 is used, OCR1 can hold values upto 65535), Task 2 is: Toggle LED connected to PB3 at 61Hz (since Timer2 OCR2 is ... |
H: What influences prepreg thickness?
I only have experience with low-speed boards that are 4 layers at most.
I want to get into full-speed USB 2.0 and 100Mb/s ethernet, so I need some impedance controlled traces. Instead of doing something professional first, I want to put together a hobby board that does these sp... |
H: Is RS-485 a suitable physical layer for Atmega chips in a home monitoring situation?
I am intending to build some Atmega based home monitoring chips. I want to monitor temperature, humidity, and current levels. Current level monitoring would be done with an inductive pickup on AC lines. Additionally I want to have ... |
H: Is the Friis Formula outdated?
It looks to me like the Friis formula is outdated. We can replace it with the E and H near field formulas, that converge into the same value in the far field.
I found it hard to use the Friis formula, whenever I switch from nearfield into farfield move, there is a sudden 20-30 dB erro... |
H: How to wire up the XP Power 8-pin isolated DC-DC converter?
I want to use the XP Power IEU0312S12 12V DC-DC converter but can't see how I should wire this.
What do they mean with "Single" and "Dual" ?
Can I put 12V on Pin 1 and 4 and then get the output on Pin 5 and 7 without connecting any external component or ... |
H: Inaccuracy in the GPS data
How can I get the inaccuracy associated with the GPS data. For example when I read lat, lon, speed, heading data from a GPS receiver, how can I get an approximation on the inaccuracy that is associated with each of these data. For example the x position might be +-10m accurate or the spee... |
H: AXI Stream Pipeline
I have following design and need to insert pipeline stage between components A and B (design doesn't meet timing constraints in Quartus II due to long data path between them)..
Simple register won't do since interface (basically simplified AMBA AXI4-Stream with START of frame signalization) bet... |
H: Is VHDL for digital circuits only?
Both Wikipedia and other SO questions about VHDL vs Verilog mention digital when describing VHDL.
Can you use VHDL to design analog circuits?
AI: Not in its base specification.
VHDL stands for V(HSIC) H(ardware) D(escriptive) L(anguage) with VHSIC standing for Very High Speed Int... |
H: Transistor Collector Heats Up
I used power transistor to drive high power LED (used in streetlights)
I added resistor between the Transistor Collector and the LED to verify which part of the transistor causing too much heat, and found out that it is really on the collector part.
Originally, the LED is powered up by... |
H: Where is the benefit in SQI parallel interface over SPI? Parallel vs. serial
Microchip is offering a number of serial SRAM chips with a communication protocol called SQI which is similar to SPI but with 4 parallel bits written at each CLK toggle.
If you can spend the extra 3 pins this makes sense. You can achieve a... |
H: Is a resistor required between VCC and Data for my temperature sensor?
I'm using a TinyDuino with a Protoboard to measure temperature with a DS18B20. I was following this tutorial but am not getting any valuable information back on the arduino when I try to read the value on the data port.
I just started reading ar... |
H: How to connect toroidal transformer from wall power
How to I connect 240v from a wall powerpoint to a toroidal transformer?
I've searched all over, and I'm a complete novice, and I cannot find anything that explains what I need to know at my level of understanding.
It is a 240v 20va 15v+15v toroidal transformer. It... |
H: Safe Power rating of resistor for my circuit
I am working on circuit shown below
Current flowing through circuit is 88.235 mAmp
I = V/R = 24/272 = 88.235mA
which generates heat of
68*88.235*88.235 = 0.529 Watt
I have used resistors of 1 watt but it generates little heat.
Will this resistor sustain for longer t... |
H: VHDL tutorial for the Lattice ECP5 Versa Development Board
I have got this Lattice ECP5 Versa Development Board and I am going to be working with it in the future. Right now I am looking for some good VHDL tutorial which will help me Play with the board and get confortable with before moving to the real Project I w... |
H: Operating an adjustable voltage regulator below minimum Vout-Vin
I used an LM350 adjustable voltage regulator https://www.onsemi.com/pub/Collateral/LM350-D.PDF and to keep the wattage dissipated by the device to a minimum I have opted to make the output voltage 24VDC. Max current drawn is around 500mA. The input vo... |
H: Individual Led vs LED Strip
I am thinking of making my own LED lamp - That is, have an array of LEDs and power them off, maybe, a battery pack? The power source I am lenient, I'll solve that issue when I get to it. My main question is regarding the LEDs
Is it more efficient to individually solder, say, 20 or 50 ind... |
H: How to write a big text on Eagle schematic?
When you choose a text from the tools bar, and put it somewhere, it will create a text that appears on the pcb.
I would like to create a text just to mark things on the schematics only, and I want it big and clear.
How do you add a big text to mark things on the schemati... |
H: how to go from eagle design to Part list
I am looking for a maintainable, shareable and scalable process to output a complete part list (as in "Part N°XXX from supplier YYY") From an Eagle project, when it seems to only be able to provides a BOM ("Component type XXX with value YYY").
Is there a way to do that using... |
H: Is acetone or isopropyl alcohol better for removing rosin flux?
For removing rosin flux from my board, should I use Acetone or Isopropyl Alcohol? I need an easily available solvent.
AI: Acetone being used to clean circuit boards can be problematic. The biggest issue that I found was that it leaves a residue in the ... |
H: Op-Amp Slew Rate
I've been searching for a very-small package op-amp and not having much luck. LTxxxxxx (edited out) would be ideal however the slew rate is just too low. Is there a way of controlling/increasing slew rate using external components?
The op-amp is used to be used as a voltage follower for 10kHz sig... |
H: Voltage regulator for Stepper and Microcontroller
I'm designing my first PCB for a personal project :
I'm planning to run a Stepper motor (3.8V 670mA/phase) with the DRV8834 driver and an Atmega328P from the same power source.
The power will come from a classic USB charger (rated at 5V, 2A) plugged in my PCB.
Do I ... |
H: measurement of differential signals using multimeter
Though differential signals are measured through oscilloscope or differential probe, i tried measuring the signals through a multimeter out of curiosity and my observation was that when a voltage was measured across Rs-485 'A' terminal and Ground, the multimeter ... |
H: How is 255 Tbit/s processed in optical fiber communication?
I have never understood how the new record breaking data transfer speeds are achieved in terms of converting from/to electrical and optical signals.
Suppose we have 255 Tbits of data and we want to transfer it in one second. (This is a real world achieveme... |
H: How can i find the source of a high pitched noise
I have one old power supply, it was dead but i decided to attempt to fix it.
Replacing all bad capacitors made it power on again.
Since i didn't had one 2200uf 10v capacitor i used one 2200uf 25v capacitor but i guess this should be fine.
but then i noticed that ter... |
H: ATMega328 attenuated potentiometer voltage
I've just got this problem:
I have a potentiometer with resistance of 50k and i have an arduino nano which has an ATMega328 IC on it.
I attached the potentiometer normally: two pins for source and gnd and one pin going to the arduino nano's analog pin.
If i turn the knob ... |
H: Analog Reading of YL 69 Soil Moisture Sensor
I am using an ESP8266 12 F Module with 3 x 1,2 V Batteries.
I tried to connect an infamous chinese soil moisture sensor YL 69 like this (LINK) to the anaolog pin of the ESP8266 Module. The Module works from 3,3 Volt on to 5 V and comes with an electronic board that inclu... |
H: turning YM T8 SMD2835 110V led light tube into USB or Battery lamp
A few days ago the electric circuit of a T8 led tube broke, but when I measured the led all were ok. Then I came up with the idea of using them in an experiment and turning them into a usb or battery lamp.
The tube consists of 30 smd led 2835 connec... |
H: Finding Alternate Comparator by Pinout?
I am using the TS391IYLT in a design, but need to swap it with an alternate that has rail-to-rail capabilities. The issue I'm running into is that the pinout is somewhat irregular; see below. Most comparators I've found have a similar pinout, but IN- and IN+ are reversed.
Is... |
H: Mouse Wheel Rotary Encoder ... encoding wrong
OK, guys - I'm pretty confused here.
I bought a cheap wireless mouse to gut and use in a project. Right now I'm trying to get the rotary encoder behaving, but (while it IS behaving) it's behaving oddly. If we call the pins 1, 2, and 3, in the mouse circuit board, 1 is j... |
H: AVR timer output when Data Direction Register set to input
This question refers specifically to an ATmega328P, but probably can be generalized to most or all AVR MCUs.
Known 1: When the Data Direction Register (DDR) for a pin is set as input mode, it is still possible to write to the PORT for that pin; instead of ... |
H: Decimate ADAR7251 Sigma-Delta ADC Output
I'm working with a Analog Devices ADAR7251 Sigma-Delta ADC. It has multiple sample rates to choose from (1800 kSPS, 1200 kSPS, 900 kSPS, 600 kSPS, 450 kSPS, and 300 kSPS) but my application requires 112.5 kSPS. I plan on using the ADC in 450 kSPS mode and will decimate by a ... |
H: Feedback factor of Armstrong Oscillator
I am trying to find an equation for the feedback factor of an Armstrong oscillator in terms of the transformer inductances and I can't find one in books.
Am I correct if I say that the feedback fraction of the oscillator is the ratio of turns of the tickler coil to the prima... |
H: Repaired a treadmill: safety check
A while ago I rented a treadmill out, and it was a high end one, with a 3HP motor. It is 240V 10A (I am in AU)
Anyway long story short, we got to keep the treadmill at the end of the rental period. The company did not want to come and pick it up from us (we tried for months to get... |
H: Altium pin error
I'm a beginner with Altium Designer 17.1 and I'm facing difficulties. I'm designing a PCB but when I compile the project this error is shown.
I'm using ports, they are set on global.
Also, I'm having another problem. I made a NMOS Schematic and this error is shown :
I made the pins and everythi... |
H: What is this type of interface?
what is this type of interface, located at the very edge of the PCB? What's interface standard, and what is pinout? The 5 holes in yellow circles is GND.
AI: That looks like half of a Mictor connector footprint for a logic analyzer. Mictor connectors are relatively high speed connec... |
H: What is the difference between characteristic impedance and input impedance in transmission lines?
What is the difference between characteristic impedance and input impedance in transmission lines? When are these quantities are equal?
AI: What is the difference between characteristic impedance and input
impedance i... |
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.