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2016-01-21 01:59:30
2018-07-01 01:34:46
[ { "message": "I'm developing a custom protocol processing device based on MCU. My protocol is somewhat similar to I2C and uses bit-banging instead of hardware implementation. I've done a prototype based on Atmega328P, mostly due to plenty of help online and cheap development boards. When everything started to w...
8051 MCU with fast entry to ISR implementation
electronics
2018-02-17T22:02:51.753
[ { "message": "How to control a voltage using PWM out of a microcontroller that can handle a load consumes 20 Amp current.. Load is a heating coil that has a resistance of 0.21 Ohms, power supply 4.2 v Li-Ion battery, PWM 0 / 3.3 volts ..", "role": "user" }, { "message": "\"Logic Level\" NFET will wo...
PWM voltage control that can handle 20A
electronics
2018-02-18T01:46:20.417
[ { "message": "Consider a two-port reciprocal network : $$ \\ Y= \\left[ {\\begin{array}{cc} 0 &amp; -1/2 \\\\ -1/2 &amp; 0 \\\\ \\end{array} } \\right]\\ $$<br>then how can we proof that it is a passive network or circuit? I have no idea how to prove it ....any hints or suggestions please...?", "...
Proof;Only Reciprocal Circuit are passive circuit
electronics
2018-02-18T09:21:35.950
[ { "message": "can anyone explain how this circuit works. A little background, this is a circuit which is used to change the switching frequency of a boost controller IC , so that it doesn't operate at a single frequency and the operation is over a range of frequencies. V2 can be thought of as a pulse coming fr...
Circuit analysis- boost controller IC frequency change
electronics
2018-02-18T19:06:28.583
[ { "message": "I don't get why the \\$\\Phi_{1}\\$,\\$\\Phi_{2}\\$ and \\$\\Phi_{3}\\$ are supposed to be running in the way depicted here.<a href=\"https://i.stack.imgur.com/ZL5yI.png\" rel=\"nofollow noreferrer\">", "role": "user" }, { "message": "Sometimes it's easier to think about magnetic circu...
What parameter is used to choose the direction of the flux in a magnetic circuit?
electronics
2018-02-19T02:29:45.820
[ { "message": "how can I generate Output 2 to give a fixed delay pulse (about half a second or less) on a rising AND falling edge of Input?<pre><code> ________________________Input ___________| |___________________ ________________________Output 1...
how can I generate Output 2 to give a fixed delay pulse on a rising and falling edge of Input?
electronics
2018-02-19T02:46:54.407
[ { "message": "I need to power an Arduino and four 4.5v-9v 2A Li-ion charger boards with a single wall adapter. Not wanting a shared circuit between the chargers, I'm thinking maybe a 12v 600mA (or something..) plug with a buck converter for each charger and powering the Arduino directly from the plug.I have no ...
Buck converter output current
electronics
2018-02-19T06:31:12.867
[ { "message": "Imagine a step response of a series RLC circuit oscillates as an under-damped way:<a href=\"https://i.stack.imgur.com/vJWCn.png\" rel=\"nofollow noreferrer\">I also came across the following equation:<a href=\"https://i.stack.imgur.com/8so5V.png\" rel=\"nofollow noreferrer\">As far as I understand...
Very basic question about under damped oscillation frequency
electronics
2018-02-19T12:45:56.253
[ { "message": "<a href=\"https://i.stack.imgur.com/0I1ob.png\" rel=\"nofollow noreferrer\">I have a problem to charge a capacitor 2200uF/400v. It takes 30 second to reach 300v. I hope can reach 300v in 10 seconds. thanks :) This my schematic:<a href=\"https://i.stack.imgur.com/O2ewJ.png\" rel=\"nofollow noreferr...
How to fast charge capacitor 2200uF/400v in fewer seconds?
electronics
2018-02-19T16:18:22.043
[ { "message": "I fixed the problem, thank you all for your help, I posted the entire circuit, for anyone in the future who has a similar problem.<a href=\"https://i.stack.imgur.com/lRi6F.png\" rel=\"nofollow noreferrer\">[![enter image description here][2]][2]", "role": "user" }, { "message": "As @di...
Mod 6 counter that counts 1-6 on a 7 segment display (FIXED)
electronics
2018-02-19T16:32:18.273
[ { "message": "I am working on creating a simple protection circuit for an I/O pin of an MCU. The input signal will be coming from an array of different devices and I will want to monitor for high/low digital values from the following input types:Reed Switch (normally open) connecting to GND when closed.Normally...
MCU Input Protection Comparison
electronics
2018-02-19T22:55:17.953
[ { "message": "I bought some RGB power leds, o.a. a Cree XML. The spec/description at the (Chinese) site mentioned forward voltage of 3.3-3.9V.But when driving the led at that voltage I measure much less current than expected. ~0.150mA @ 3.9V instead of ~1A for the Cree led, and something similar for other leds ...
Current too low at forward voltage of power led
electronics
2018-02-19T23:04:38.570
[ { "message": "I have an elementary question about current flow:If I connect a simple 1.5 V battery to a hypothetical LED of 1.5 ohm and an ideal ammeter, the ammeter would show a current of 1 Ampere and the LED would glow (let us assume the power is enough).Now, instead if:---------- 1.5 ohm LED ----- ideal amm...
Basic: Current flow and grounding
electronics
2018-02-20T00:20:42.717
[ { "message": "Here is an example how to define the 2*N array of enum types of {S0,S1,S2,S3}:typedef enum logic [N-1:0][1:0]{S0,S1,S2,S3} state_t; (*)So, each element of the above 2*N array could be either S0 or S1 or S2 or S3.Let's say the {S0,S1,S2,S3} are defined as a separate enum type:typedef enum {S0,S1,S...
SystemVerilog Enumerated Multi-Domain Array -> how to declare/define?
electronics
2018-02-20T00:49:23.487
[ { "message": "I am trying to place a variable named secret_key at location <code>0x08002000</code> in STM32Nucleo-board which has STM32L476RG on board with 1MB flash.Question 1: Why am i unable to place code in custom ROM (<code>SECRET_IROM1</code> )section?<br>Question 2: What is the mistake i am doing?I am st...
Placing a key variable in internal flash Memory
electronics
2018-02-20T05:35:36.990
[ { "message": "We are using a stepper motor which has a rated voltage of 2.7V and resistance of 2.7 ohms. This means that the rated current is 1 A. We have also set the current limit of the DRV8825 motor driver to 1A. We are running the motor with a 24V power supply. On the multimeter, the current value doesn't ...
Stepper Motor drawing very low current from DRV8825
electronics
2018-02-20T05:50:12.297
[ { "message": "Hey I got a question about switching a 12V supply to a low power circuit with an MCU.My requiaments are: - switching has to be on the High side. - switch should stay \"closed\" when MCU is powered down. - MCU is TTl level (Atmega 328P)After some searching I came up with this shematic but I don't k...
12v PNP- switching with MCU
electronics
2018-02-20T09:53:10.940
[ { "message": "I have a book which is giving a brief solution to a theoretical question, it is skipping some steps of the solution,these missed steps seems to be important to me to understand them.I recite them below and i would like some help for a more detailed solution without skipping steps.Question 1:$$give...
sinusoidal signal, computing its power
electronics
2018-02-20T10:40:43.030
[ { "message": "I want to switch several (10-20) relays with a raspberry pi.I will use darlington arrays like the ULN2003 to drive the relays, and a shift register to not use up all of my GPIO pins.I will use an external 5V power source just to be extra safe, in case I switch all the relays at once.Since the rasp...
shift register that accepts 3.3V to drive several 5V relays
electronics
2018-02-20T17:51:01.557
[ { "message": "This circuit is made of one differential BJT transistor pair and voltage-amplification stage with negative feedback.<a href=\"/plugins/schematics?image=http%3a%2f%2fi.stack.imgur.com%2fHWq0y.png\">simulate this circuit &ndash; Schematic created using <a href=\"https://www.circuitlab.com/\" rel=\"n...
Differential Amplifier's Unusual Behavior
electronics
2018-02-20T19:51:19.923
[ { "message": "This circuit is made of one differential BJT transistor pair and voltage-amplification stage with negative feedback.<a href=\"/plugins/schematics?image=http%3a%2f%2fi.stack.imgur.com%2fHWq0y.png\">simulate this circuit &ndash; Schematic created using <a href=\"https://www.circuitlab.com/\" rel=\"n...
Differential Amplifier's Unusual Behavior
electronics
2018-02-20T19:51:19.923
[ { "message": "I intend to run a 48V DC water pump which uses this motor (<a href=\"http://www.leeson.com/leeson/searchproduct.do?invoke=viewProductDetails&amp;motorNo=098382.00&amp;productType=0\" rel=\"nofollow noreferrer\">http://www.leeson.com/leeson/searchproduct.do?invoke=viewProductDetails&amp;motorNo=098...
Selecting Flyback Diode for Inductive Load
electronics
2018-02-20T21:52:23.040
[ { "message": "I want to use an inverting amplifier to linearly shift and convert a signal with voltage range -10...+10V into 0 ... 3.3V for an ADC of a microcontroller. I wanted to use the circuit presented in <a href=\"https://electronics.stackexchange.com/a/98315/178148\">this post.<a href=\"https://i.stack.i...
Supply Voltages for Inverting Amplifier
electronics
2018-02-20T22:53:18.867
[ { "message": "I want to drive a 12v DC motor that will rotate an array of small solar cells to track the sun across the sky. I intend to use two smaller solar cells as my sun \"position sensor\" by having them at an angle to each other so as the sun moves West, the output voltage will change with the motor dri...
LM311 Op Amp as a differential amplifier to drive a solar tracking motor
electronics
2018-02-21T01:21:16.257
[ { "message": "I am trying to interface my STM32 with NRF24[2.4 Ghz ] or TICC2500[2.4 Ghz] models. I am finding issue regarding maximumallowable Bandwidth and RF power set by ETSI[Europe] EN 300 328 and EN 300 440(Short Range Devices[SRD])regularity body. Kindly if someone have knowledge regarding thisplease sha...
ETSI[Europe] Regulations for 2.4Ghz ISM Bandwidth Limit and RF Power
electronics
2018-02-21T08:01:04.323
[ { "message": "not sure if this is an EE question, it's the closest SE site I could see?I have a Sony separates mini-system (HCD-SD1) I was given; it's quite old now but good. Except that for a while now, when I turn it on sound only comes through one speaker. After a few (~5) minutes the other speaker will kick...
Why does one of my HiFi speakers only start working after several minutes?
electronics
2018-02-21T10:38:28.123
[ { "message": "I have a circuit where a 5.055V 2.17A (MAX) DC circuit is supposed to be switched using a 3.404V 0.99A(MAX) DC source.Theoretically, 3.404V 0.99A between base and emitter should allow quite a large current to pass from collector to emitter, but when I am using BC548 B type (Min theoretical gain 20...
What are the real world limitations of using a transistor as a switch?
electronics
2018-02-21T11:53:21.467
[ { "message": "I have an LM317AHVT power supply with PNP pass transistor.I noticed that the power transistor is heating up to about 64C after a few minutes. I am using an 130x80x30mm heatsink and an 92mm fan to cool the heatsink. The temperature of the heatsink is about 46C.I mounted the transistor using mica in...
Transistor heating up problem
electronics
2018-02-21T15:26:48.323
[ { "message": "I have a simple problem, I got stuck with it.<a href=\"/plugins/schematics?image=http%3a%2f%2fi.stack.imgur.com%2fekS5i.png\">simulate this circuit &ndash; Schematic created using <a href=\"https://www.circuitlab.com/\" rel=\"nofollow\">CircuitLabI have to plot the voltage drop on resistor R as a ...
Different voltage sources in parallel with a diode
electronics
2018-02-21T18:01:18.953
[ { "message": "So I'm reading up on MPP, and I don't get it.Let's say there's solar panel, now there's flow of electrons from solar panel, correct? That's how you get so-called \"power\" into the battery, right?I don't get what's the point of Boost converter, if you just simply need to hook solar panel to batter...
Maximum power point, why do you need to change voltage again? Isn't it simply \$ P = i^2 \cdot R \$?
electronics
2018-02-22T02:35:56.763
[ { "message": "I have been working on a little project of mine in which I try cool a small peltier using this laptop heat sink fan. The peltier I am using is rated 10W, while the laptop fan is rated for 18W of thermal dissipation.I have noticed that there are certain \"modifications\" that can be tone do laptop ...
Modding Copper Heatsink - Fans for Better Heat Dissipation
electronics
2018-02-22T05:13:48.150
[ { "message": "My question is mostly if I am doing it right.I have a <a href=\"https://www.elenco.com/brand/snap-circuits/\" rel=\"nofollow noreferrer\">snap circuit kit (kinda like a breadboard for kids). I also have a <a href=\"http://circuitgizmos.com/gizmo-store/#!/CGCOLORMAX2-Color-Maximite-Retro-Computer/p...
Using a transistor correctly to "connect" Maximite computer and circuit
electronics
2018-02-22T17:13:47.943
[ { "message": "I have a question on Inductors for VHF Amplifiers and Transmitters. I often see circuits on the web, where several aircore enameled copper wire inductors are used. The specification looks something like this:L1 = 5 Turn 26 SWG Enamelled Copper 10mm diameter aircoreI understand all the attributes o...
How to select alternative inductors for High Frequency Amplifiers
electronics
2018-02-22T17:25:46.030
[ { "message": "One of the most recent memory architectures is the 3D-Xpoint which has a structure of the type:<a href=\"https://i.stack.imgur.com/wrpLW.png\" rel=\"nofollow noreferrer\">So, you see that as usual in a memory device we have wordlines and bitlines.Now suposse I want to access one of the cells. For ...
Memories' structure
electronics
2018-02-22T18:19:46.643
[ { "message": "First off, since this is my first post (I am a long time answer seeker), I would like to thank the SE EE community for all the answers I got here over the years! Thanks!Being self-taught, I've always gotten by on research and reading but this time I am stalled.I want to build a DC-DC step-down pow...
Wondering if my protective diode is sufficent
electronics
2018-02-22T18:53:17.367
[ { "message": "I bought 2 anti-static gloves and 1 grounded wrist strap to protect the parts against ESD by assembling computers. I was wondering whether a single wrist strap is enough, because I use to touch parts with my right hand too.", "role": "user" }, { "message": "As the question written, \"i...
Is a single wrist strap enough against ESD?
electronics
2018-02-22T19:16:54.157
[ { "message": "I am am reading ADC via DMA on the STM32 Nucleo F334R8. However, after I start the DMA using the code below, the main while loop fails to execute<pre><code>HAL_ADC_Start_DMA(&amp;hadc1, (uint32_t *)&amp;ADC_Raw, 4);</code></pre>I understand that the DMA interrupts may be occurring so often that it...
ADC DMA on STM32, Nucleo F334R8 stops main while loop from executing
electronics
2018-02-22T20:18:35.933
[ { "message": "I'm doing some modeling of LV networks, using meter data (AMI) giving me instantaneous values for real and reactive power, in 5-minute intervals. I am seeing a lot of negative reactive power, which I am interpreting as indicating leading power factor. This is not what I expected to see. This is ha...
Leading power factor for residential customers
electronics
2018-02-23T05:10:31.040
[ { "message": "We are using a ST10F269Z2T3 Microcontroller <a href=\"http://www.st.com/content/ccc/resource/technical/document/datasheet/99/3b/0f/d2/28/ab/4f/8e/CD00152495.pdf/files/CD00152495.pdf/jcr:content/translations/en.CD00152495.pdf\" rel=\"nofollow noreferrer\">(Datasheet) in one of our old Designs. Amon...
ST10F269Z2T3 abnormal Input Logic Levels
electronics
2018-02-23T10:01:10.547
[ { "message": "I collected experimental data of input and output characteristics of a BJT NPN in Common Emitter configuration. I need to find the right function to fit the Ic vs Vce, but I'm not finding it. I've used the Shockley Equation with no luck. I have tried the Early model and it worked fine on the linea...
Formula for BJT common emitter output characteristics curve
electronics
2018-02-23T12:12:13.403
[ { "message": "I am trying to understand batteries. 1) If I have a rechargable battery of 1.2 V 1000mAh, it means I can draw 1A at 1.2 V for one hour and the battery is said to be discharged ? Does \"discharged\" mean 0 volts and so I can't draw anymore current from it ? 2) Can I recharge this battery by simply ...
Basics of battery charging and discharging
electronics
2018-02-23T12:15:23.667
[ { "message": "Lets say we have this circuit:<a href=\"https://i.stack.imgur.com/Eq3q8.png\" rel=\"nofollow noreferrer\">tpd(AND)=5 ns, tpd(OR)=5ns, tpd(NOT)=3ns, and tcd of all gates =1nsFlipFlops: tpcq=1ns, tccq=1ns, tsetup=1ns thold=1nsFirst I want to check this circuit for hold-time violations. And then I wa...
How to calculate latency of a circuit?
electronics
2018-02-23T12:46:26.347
[ { "message": "I created an AM modulator circuit with BJT 2N3904 for a school project.<a href=\"https://i.stack.imgur.com/93vUP.jpg\" rel=\"nofollow noreferrer\">V1 is the modulating signal (sine wave, amplitude 5V, frequency 1KHz)V2 is the carrier signal (sine wave, amplitude 30mV, frequency 600KHz)With Tina si...
AM Modulator with BJT 2N3904
electronics
2018-02-23T14:24:50.603
[ { "message": "I solved this using delta star transformation (Zeq = 2/3 ohm), but I can't find other circuit analysis techniques to find the Zeq &amp; Io, any help? <a href=\"https://i.stack.imgur.com/K6blf.png\" rel=\"nofollow noreferrer\">", "role": "user" }, { "message": "Use the <a href=\"https:/...
Other ways to solve this other than Delta Star Transformation
electronics
2018-02-23T16:35:38.900
[ { "message": "I'm developing USB Hibernation feature on on of the platform which use Synopsis DWC3 USB controller. When USB alone resumes from suspend state there is no issue.But I'm facing an issue while my device is resuming from deep sleep. While resuming the Link state comes as 4 (Disconnected) which leads ...
USB Link state is dissconnected while exiting from deepsleep
electronics
2018-02-23T16:51:55.800
[ { "message": "I was building an ESC. Motor V=22V max current I=90A Battery max current I=60A. My controller is a MIC4607 (Datasheet:<a href=\"http://ww1.microchip.com/downloads/en/DeviceDoc/20005610B.pdf\" rel=\"nofollow noreferrer\">http://ww1.microchip.com/downloads/en/DeviceDoc/20005610B.pdf)The PWM f=16kHz ...
PCB Shunt BLDC controller current sens
electronics
2018-02-23T18:23:52.160
[ { "message": "How should I choose a power supply for a stepper motor, if the motor requires 7V and 1A? Should I buy a power supply of exactly 7V and current of minimum 1A?", "role": "user" }, { "message": "<a href=\"http://akizukidenshi.com/download/ds/towerpro/SG90.pdf\" rel=\"nofollow noreferrer\"...
How to choose power supply
electronics
2018-02-23T18:49:59.380
[ { "message": "I came across the following circuit on net which is a simple RF/cellphone signal detector:<a href=\"https://i.stack.imgur.com/sePyP.png\" rel=\"nofollow noreferrer\">Before I build and try I decided to simulate it in LTspice as follows:<a href=\"https://i.stack.imgur.com/PCiBq.png\" rel=\"nofollow...
Simple model for a loop antenna for LTspice simulation
electronics
2018-02-23T20:19:18.233
[ { "message": "This might sound like a stupid question, but I'm kinda interested in a detailed explanation.So while inductive charging is rather ubiquitous, things like electric toothbrushes and Qi chargers come to mind, as well as to a lesser extent, wireless charging pads for cars, the are all inductive chargi...
Using a capacitor instead of a coil for wireless charging?
electronics
2018-02-24T11:45:14.197
[ { "message": "Are there any any IC s (like bidirectional current sensing ic s) or sensors that can measure high voltage like 60-70 volt and conver it to equivalent 0-5V . Also the current rating is high 70-85 ampere. This is to make a battery level indicator for 60V 100 AH li-ion battery.", "role": "user" ...
Are there IC /sensor/module/microcontroller to measure voltage upto 60 volts or high current like 75 ampere
electronics
2018-02-24T12:04:54.983
[ { "message": "Follow-up to: <a href=\"https://electronics.stackexchange.com/questions/357636/\">Is it okay to use a MOSFET in its resistive region with a heat sink?I plan to use two PWMs to very slowly (exponentially) turn on an LED strip, from 0.002% to 0.004%... to 100% power over twenty minutes. 0.002% seems...
Combining two PWM outputs for finer granularity
electronics
2018-02-24T13:39:51.043
[ { "message": "I'm using and Arduino, an IR Led, and a transistor to for sending RC5 signals (36khz).For the next step I need to be able to adjust the brightness of the signal, basically changing the range. The value could be set by an analog signal, spi or i2c or anything basic.I thought about using a digital p...
Adjustable brightness for IR remote signals
electronics
2018-02-24T20:47:05.110
[ { "message": "I am designing a driver circuit to drive a hydraulic proportional valve froman IC's PWM output. (IC is ATmega 2560). The coils on the valve draw approx 3Ampsat %100 duty cycle with a power supply of 28v.MOSFET's seem to be the way to accomplish this, thou I am struggling to find a 'safe' solution....
Driving inductive load from IC with MOSFET
electronics
2018-02-25T04:05:32.707
[ { "message": "New to designing circuits and PCBs. I'm working on a project and I can't seem to figure out how exactly how to do what I'm trying to do. I'm hoping one of you can give me a hand understanding the concept behind a few things I just can't seem to wrap my head around.Basically, I'm designing a PCB fo...
Batteries in parallel and series. Auto disconnect load while charging
electronics
2018-02-25T05:33:30.823
[ { "message": "I have a radio signal source (USRP N210 with a WBX daughterboard) that can supply a maximum power of 100mW. I am designing a power amplifier for it and I would like to simulate the radio signal source in Spice. What is the equivalent circuit ( maybe the Thevenin equivalent) of the radio signal sou...
Equivalent circuit for a radio power source (USRP)
electronics
2018-02-25T07:12:51.373
[ { "message": "This is a memristor-based IF neuron circuit.My question is, i'm trying to simulate this circuit in PSPICE. However, I am unsure what the N-MOSFET characteristics (M1) are in the circuit diagram. I do not see any parameters in the paper. Do I just choose an arbitrary N-Mosfet from the mosfet librar...
(PSPICE) Memristor-Based IF Neuron Circuit: What is this NMOS?
electronics
2018-02-25T07:36:03.887
[ { "message": "I am trying to measure vertical and horizontal speed of an object attached to a parachute. It will be launched from a low altitude and in an open area, allowing satellite GPS lock.Data treatment will be post flight, so no real-time or processing power requirements.Up to now, I have identified two ...
Optimal sensor for measuring object velocity in an open area?
electronics
2018-02-25T09:37:19.987
[ { "message": "I am new to Electronics. I am trying the Full wave rectifier.I use a transformer and 4 1n5408 diodes (Vdrop is 1.2V) and try to get 24VDC output from 220VAC 50Hz. I measure the AC output (of the transformer) and it is 24VAC. I measure the output after these 4 diodes, it is about 23VDC.Everything g...
Smoothing capacitor burns out while I am trying full wave rectifier
electronics
2018-02-25T14:46:39.003
[ { "message": "Background:I am designing a small Arduino-driven circuit to control a ~3/4 hp AC hoist motor. The hoist motor includes a starter-capacitor. The Arduino drives a transistor which in turn drives a power relay that switches the motor on and off. I am not an electrical engineer, so I'm using a Factor ...
How to wire a high-current relay?
electronics
2018-02-25T20:42:06.697
[ { "message": "Another word for potential difference, is apparently, \"<a href=\"https://www.electronics-tutorials.ws/dccircuits/dcp_1.html\" rel=\"nofollow noreferrer\">voltage drop\", although I've heard potential difference be interchangeable with just voltage, as well, a bit confusingly. However, if I unders...
Why does high voltage imply a high "pushing force" on electrons?
electronics
2018-02-26T02:05:13.383
[ { "message": "I'm not used to working on Altium Designer(17.1). I couldnt find how can I export only pad layouts to making a stencil schematic. It is good to export as a pdf file if it possible.", "role": "user" }, { "message": "In a PcbDoc go to File -> Fabrication Outputs -> FinalThere you get a p...
Export pads as a pdf file in Altium
electronics
2018-02-26T07:45:14.290
[ { "message": "I know that a transmission line is essentially two wires with some series resistance and inductance and some parallel capacitance - when there is a change in the voltage between them at a point the charge in the capacitance moves and thus a current is flowing in opposite directions in both wires. ...
Unequal length Transmission line
electronics
2018-02-26T13:47:12.307
[ { "message": "I was calculating ESR for this ceramic capacitor, Samsung P/N <a href=\"http://www.samsungsem.com/kr/support/product-search/mlcc/__icsFiles/afieldfile/2016/08/18/S_CL21A226MQQNNWE.pdf\" rel=\"nofollow noreferrer\">CL21A226MQQNNWE.Per the datasheet, DF is given as 0.1 max at 120 Hz.Per formula, ESR...
Unrealistic ESR calculated from DF
electronics
2018-02-26T17:27:55.393
[ { "message": "I was calculating ESR for this ceramic capacitor, Samsung P/N <a href=\"http://www.samsungsem.com/kr/support/product-search/mlcc/__icsFiles/afieldfile/2016/08/18/S_CL21A226MQQNNWE.pdf\" rel=\"nofollow noreferrer\">CL21A226MQQNNWE.Per the datasheet, DF is given as 0.1 max at 120 Hz.Per formula, ESR...
Unrealistic ESR calculated from DF
electronics
2018-02-26T17:27:55.393
[ { "message": "I have a PCB with 3 inputs:Ground5V (logic IC power supply)User-selectable 5V or 12V (motor power supply)There are two types of motors, 5V and 12V. If the user selects the wrong DIP switch up-stream (12V instead of 5V) the motor will blow up. The user-selectable input is directly connected to a du...
Overvoltage protection circuit
electronics
2018-02-26T19:28:05.947
[ { "message": "Is that possible? It is an Saia UFR1 motor running on 220V. <a href=\"https://oc.kosmospora.de/index.php/s/gp3szJXgk3P0SMP\" rel=\"nofollow noreferrer\">https://oc.kosmospora.de/index.php/s/gp3szJXgk3P0SMPCan I simply use a double relais shield? EDIT:The motor is part of a valve actuator of my hea...
Control 220V stepper motor with arduino?
electronics
2018-02-26T20:25:16.927
[ { "message": "I share the picture of the schematic of my circuit. I want to use the LM350 variable voltage regulator to reduce the 40mV p-p ripple i have in my bridge rectified DC. Though it has no effect at all. Why could this be?My load draws current and i can adjust the voltage output of LM350. I couldn't m...
LM350 not reducing the ripple
electronics
2018-02-26T21:36:17.570
[ { "message": "I'm designing a current source using a MOSFET driven by an opamp. The opamp controls the gate by comparing the voltage on a shunt resistor to the input reference. You could say that the fet replaces the feedback resistor in the standard non-inverting configuration. I know the bandwidth I require, ...
gain of opamp circuit with current output
electronics
2018-02-26T23:48:48.353
[ { "message": "I would like to design a flexible input interface for my embedded device, which will see a mixture of sensors connected. The sensors themselves (e.g. thermistors) will be two-wire, with the data/signal wire being pulled up to 5V prior to interfacing with an ADC. The issue I'm trying to address is ...
Input flexibility for powered vs. unpowered sensors
electronics
2018-02-27T00:33:25.607
[ { "message": "I am trying to amplify an audio signal generated by a hydrophone. I am trying to work from this (very general) circuit diagram I have found online and in an electronics textbook I own.<a href=\"/plugins/schematics?image=http%3a%2f%2fi.stack.imgur.com%2fvDtcw.png\">simulate this circuit &ndash; Sch...
lm318n as noninverting amplifier
electronics
2018-02-27T06:45:33.647
[ { "message": "I want to use anti-aliasing filters in different scenarios. Below is the topology for how to use a passive LP filter in the case of a single ended transducer and single ended data acquisition:<a href=\"https://i.stack.imgur.com/zJox4.png\" rel=\"nofollow noreferrer\">How should the RC the connecti...
Using low pass filter for a differential ended receiver system?
electronics
2018-02-27T11:53:09.867
[ { "message": "Requirement: Need to use only accelerometer in LSM6DS3 at 104 Hz in 2g full-scale mode and FIFO in Continuous mode. Interrupt should be generated every 320 msec.Understanding: For every 1 sec there are 104 samples (104 \"X\" samples, 104 \"Y\" samples and 104 \"Z\" samples, 2 bytes each) i.e. 624 ...
Interrupt and FIFO settings in LSM6DS3
electronics
2018-02-27T13:19:19.587
[ { "message": "(see update at the end)This is a continuation of my previous question about a relay: <a href=\"https://electronics.stackexchange.com/questions/358702/how-to-make-a-pcb?noredirect=1#comment862399_358702\">QuestionWhat I want is a notification LED for both power and if a switch is on, which controls...
Relay with notifications circuit
electronics
2018-02-27T21:49:26.060
[ { "message": "(see update at the end)This is a continuation of my previous question about a relay: <a href=\"https://electronics.stackexchange.com/questions/358702/how-to-make-a-pcb?noredirect=1#comment862399_358702\">QuestionWhat I want is a notification LED for both power and if a switch is on, which controls...
Relay with notifications circuit
electronics
2018-02-27T21:49:26.060
[ { "message": "I have searched the AtTiny data sheet and not found anything about this. I'm experiencing a weird PWM bug. When I expect 100% on I'm getting less. I'm using an inverted PWM scheme, so setting it equal to 0 should be full on, but my scope shows a ~95% on duty pulse.Below I posted applicable setup c...
Attiny4 - Possible Errata Found With PWM
electronics
2018-02-28T02:20:56.313
[ { "message": "We all know that the purpose of Bridge rectifier is to change the AC to DC,and the picture below is my assumption,and as i know ,the Q1, Q2, D2 and the first level RC circuit are the filter and voltage stable mechanism,so i think the circuit in the red square is the voltage stable mechanism.but i ...
How the voltage stable mechanism work in Bridge rectifier?
electronics
2018-02-28T03:29:29.670
[ { "message": "I am using opamp as an integrator and found one reference design in which Vin is given at negative terminal and 2.5V is given at positive terminal, in that case how Vout can be calculated and what will be the mathematical expressions ?", "role": "user" }, { "message": "Assuming this is...
What is the effect of input on positive terminal of integrator?
electronics
2018-02-28T05:13:08.010
[ { "message": "I'm working with a project to collect temperature data from about 50 cabins that are located close together. It therefore seems easiest to use 50 Lora nodes with temperature sensors and one gateway.So I'm searching for a way to use multiple Lora nodes to create a sensor network. From what I've gat...
Creating a LoRaWAN gateway with multiple nodes?
electronics
2018-02-28T13:51:37.163
[ { "message": "I bought a DPS5005 unit in order to setup a cheap power supply. The module seems to be quite popular and has often been described as remarkably good for its low price of about 35 $. However, even under load (2 A flowing through a 0.1 Ohm resistor) I get short 450 mV peaks at a frequency of 35 kHz....
LC-Filter for DPS5005 power supply
electronics
2018-02-28T15:32:05.200
[ { "message": "All other variables being equal, how does waveform complexity of a plane wave affect shielding effectiveness? Is it easier to attenuate a sine wave or a complex waveform?", "role": "user" }, { "message": "Any \"complex waveform\" is a superposition of \"sine waveforms\". Therefore eac...
Is it easier to attenuate a sine wave or a more complex wave?
electronics
2018-02-28T15:41:53.043
[ { "message": "I have done research on different batteries and cannot find a maximum OR minimum voltage to keep NiMH AA batteries within. It seems that typically battery chargers will measure the negative voltage CHANGE or the temperature, but are not designed to hit a certain voltage limit. I have seen some c...
What is the recommended fully-charged voltage for NiMH AA batteries?
electronics
2018-02-28T16:12:40.557
[ { "message": "I'm using the following circuit for a half wave rectifier. I have the following values:R1 and R2 = 1K,Vin: 400mv peak to peak, 60 Hz (it's a sine plus noise)D1 and D2: 1N4007Op amp: LM 741. Positive supply for op-amp is 5V and ground for negative voltage. The circuit works as expected with these v...
Op Amp peak detector not working
electronics
2018-03-01T04:48:34.020
[ { "message": "<a href=\"https://i.stack.imgur.com/hENJy.png\" rel=\"nofollow noreferrer\">Hello, I have the circuit shown above. Its made to measure analogue voltages up to 10V and converting currents up to 20mA to a voltage output. 10V or 20mA = ~3.3V outputNow I want to test the voltage measurement functional...
Circuit with Zener-Diode not working (simulation do)
electronics
2018-03-01T09:13:54.510
[ { "message": "I made some jitter measurements of my high speed serial link yesterday. Now i'm analysing the jitter sources, and found out, my random jitter is often not around zero, most time about -1 .. -0.5ps.What's the reason for a not 0 mean of the random jitter?<a href=\"https://i.stack.imgur.com/SweDS.png...
Jitter measurement in High speed serial link - Random jitter mean not 0
electronics
2018-03-01T09:32:14.507
[ { "message": "I am trying to understand the following tuned collector feedback oscillator extracted from <a href=\"http://www.nutsvolts.com/magazine/article/bipolar_transistor_cookbook_part_5\" rel=\"nofollow noreferrer\">here using LTSpice. I understand that L1 and C1 creates the resonance at the oscillation f...
Operation of tuned collector feedback oscillator
electronics
2018-03-01T10:09:51.967
[ { "message": "I am developing a <a href=\"https://en.wikipedia.org/wiki/Digital_Addressable_Lighting_Interface\" rel=\"nofollow noreferrer\">DALI Control Device using STM32 board. I have already programmed the board to send DALI Slave commands according to DALI Protocol. But I am facing problem interfacing my b...
DALI Click Board: Not clear about the board operation, usage and circuit design
electronics
2018-03-01T10:58:40.263
[ { "message": "As suggested how do you feed a Dipole antenna with single ended RF IC. I found tons of examples single antenna Line feeding a differential RF port on IC but not other way round. What I want to do is feed a PCB DIPOLE antenna with singled ended feed from the IC and match the impedance. I have consi...
Feeding a PCB dipole with single ended RF signal
electronics
2018-03-01T11:13:33.987
[ { "message": "I've managed to adapt a basic multivibrator circuit to contain 3 LEDs that blink in sequence, but I want to be able to control which LED lights first when it's turned on, so the same LED lights first every time.Is it possible to bias which transistor turns on first by tweaking the values of the re...
Controlling which transistor turns on first in a multivibrator
electronics
2018-03-01T16:31:33.980
[ { "message": "I'm looking to build a component (simulink) that cuts off short pulses in a digital signal (that has a varying pulse length). Does anyone have an idea?I thought about using an integrator and comparing the output value to a calculated value that would be the integral of the shortest pulse I want to...
short pulse suppression
electronics
2018-03-01T19:46:46.980
[ { "message": "I have an I2C device that I know the address is 0x70 (probed when connected to Raspberry Pi using i2cdetect -y 1). My issue is that the bytes I want to look at need to be called in WiringPi. The output string is seven bytes long and WiringPi looks at the device address and then looks at the byte a...
I2C Addressing after device address is known
electronics
2018-03-01T19:50:43.200
[ { "message": "I am starting to work on undergraduate project to build electric skateboard. Main thingI will foucus on, will be ESC (electric speed controler) made for a motor 190KV <a href=\"https://diyelectricskateboard.com/products/electric-skateboard-motor-6355-190kv\" rel=\"nofollow noreferrer\">(motor spec...
Designing from low-voltage 3-phase motor driver for more powerfull BLDC motor
electronics
2018-03-01T22:12:56.423
[ { "message": "I want to drive an ADC with an OpAmp (LT1819). The op-amp is in non-inverting configuration driving the ADC pseudo-differentially.The filter between opamp and ADC should be (\"the specs\"):passive-3dB at 100 MHz, 3rd order Butterworth or Bessel (or steeper)not load the Opamp too much (RL >1k)keep ...
Ladder filter without termination resistor?
electronics
2018-03-01T22:31:45.910
[ { "message": "I want to drive an ADC with an OpAmp (LT1819). The op-amp is in non-inverting configuration driving the ADC pseudo-differentially.The filter between opamp and ADC should be (\"the specs\"):passive-3dB at 100 MHz, 3rd order Butterworth or Bessel (or steeper)not load the Opamp too much (RL >1k)keep ...
Ladder filter without termination resistor?
electronics
2018-03-01T22:31:45.910
[ { "message": "I have some questions about using capacitors with an L7805CVAccording to the <a href=\"http://datasheet.octopart.com/L7805CV-STMicroelectronics-datasheet-7264666.pdf\" rel=\"nofollow noreferrer\">datasheet, on page 4, it shows I need:C1 = 0.33 uFC0 = 0.1 uFI bought a few sets some time ago with 'c...
Capacitors for 7805CV?
electronics
2018-03-02T00:02:18.410
[ { "message": "I am designing a low-cost ($5) transceiver based remote system, that uses a CC110L or rfm22b type transceiver (i.e. low cost). What are some cost-effective, yet high performance antenna options? My goal here is to maximize range (minimize antenna losses), and range is more important than bit-rat...
What is a good low cost antenna design for a low cost 433 MHz transceiver?
electronics
2018-03-02T03:31:01.300
[ { "message": "I want to design a circuit which will copy a current from another circuit without affecting that circuit current. An input circuit there is some current through a resistor or path I want to follow that current and will output through a load (load resistance may independent). How to design that cir...
How can i design a current follower that can copy current without affecting the circuit current?
electronics
2018-03-02T05:16:19.180
[ { "message": "Iam relatively new to electronics, and I am building a prototype from an Arduino board. I see that I can control a relay from an Arduino. However the problem is - the relay I am using is active low. So I decided to use a inverter - ICIC7404. But in this <a href=\"https://electronics.stackexchange....
74HC540 vs 7404
electronics
2018-03-02T09:53:23.507
[ { "message": "I'm looking at an LPC812 Cortex M0+ microcontroller and its GPIO functions. On a PIC microcontroller, one would always set the LATch prior to changing the direction of a given pin. This avoids the possibly nasty situation where a pin \"gitches\". ie: the output state of the pin is a 1 just before ...
Changing pin direction without glitching on LPC800
electronics
2018-03-02T11:50:55.520
[ { "message": "I've prototyped a simple circuit for interfacing a ceramic mic to an iPad. It uses a 2N5457 JFET. I just happened to have that component on hand and it worked well. I'd like to implement this circuit using a surface-mount JFET, but frankly don't have the expertise to pick out one which is likely t...
Choosing an SMD JFET
electronics
2018-03-02T16:19:59.153
[ { "message": "If the capacitor plates are not ideal conductors (and have relative dietetic constant > 1), how does that change the capacitance calculations? It is my understanding that capacitance is purely related to geometry and the material BETWEEN the plates and not the plates themselves, is that correct? (...
Non-ideal conductor in a capacitor
electronics
2018-03-02T19:44:48.980