Questions tagged [switching]
Switching can be defined as the change in state whether it be an analog, digital, or mechanical device. For digital devices, switching can be defined as a transition from HIGH to LOW or vice versa. For analog devices, switching can be defined as a change of operation within a transistor. Mechanical device examples include physical light switches or button switches. Ultimately, switching interrupts current from going into another conductor path.
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If I use NC contact, could I avoid oxidation on the contact?
If I use the NC contact of a limit switch for micro load switching(24 V, <0.1 mA), could I avoid oxidation on the contact?
Because the contact will be closed and air will not reach it.
I have to ...
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Can I use a MOSFET switching circuit to trigger a digital input (that reads +24 V as high) with an Arduino Mega 2560 R3?
Its my first time posting.
I need to trigger a digital input pin on an industrial KUKA robot with an arduino. The pin reads +24 V as high. I'm using the circuit below. It consists of an IRL520 N-...
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Best way to switch electronically between different voltage sources for measurement
I am trying to make a circuit that can measure voltage between three different terminals. The Voltage under measurement can range upto 0 to 1500V.
As you can see in the circuit, I want to Measure the ...
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Switch Power Supply at 24V using MOSFETs
As title, here's a schematics:
simulate this circuit – Schematic created using CircuitLab
Is this a correct way to create a power switch or can this schematic be improved?
Board will sink at ...
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Negative Half of Sine Wave Passes Through Off MOSFET
I'm trying to design a MOSFET based switch which allows a sinewave through, however I noticed that when I was simulating it in LTSpice, whenever I try to turn off the FET the negative half of the ...
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LM2678 PCB Layout question / review
After my initial question about switching regulators I had decided on trying to use an LM2678 for an adjustable/variable voltage form 5-24V and 5A max with an input of ~30VDC.
The application will be ...
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Turn On Relay by Phone Line Power
I have two corded phone lines that I want to connect both of them to one telephone device. The phone must be connected to line 1 by default, and it switches to line 2 when it rings. I made a simple ...
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Simplest way to switch inductive load with an Arduino?
I'm trying to switch (just on/off) a 3.7V motor (coil resistance 2.2 ohm) and a 6V motor (coil resistance 8 ohm) with an Arduino Mini.
I have trouble finding a universal way to do so.
What I know so ...
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Switching high voltages with MOSFET at high frequencies
I need to rectify 220V 50Hz AC power to obtain 48V DC output voltage. Up to 40A current can be drawn from the DC side. 10% ripple is acceptable on the rectified voltage.
I am considering two ...
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What does 50%TTL - 10/90% RF mean for a switching speed measurement?
I understand what switching speed is and why it's important, but I'm confused on the description of switching speed that I commonly see in part specs, like the one below:
Diode Spec with Switching ...
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switching power supply pcb layout
I'm studying for the best practice to route a switching dc to dc step down regulator. Particularly this TI part.
On page 37 there's a layout example.
I was wonder if it could be any problem to place ...
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Peak power pulse in parallel MOSFETs
I have a circuit like the one shown below. To make the schematic easier to read, I only show 2 FETs in parallel. I actually have 8 identical FETs in parallel. The HT0440 is a high-side N-channel FET ...
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Can I use a push button switch to operate an actuator?
Please forgive me if my question is just silly. I'm really struggling to find answers.
I have bought what I believe to be a DPDT switch. It is however a push button switch. It is an 8 pole switch with ...
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DC to AC welder accessory circuit
I want to create an external accessory for a DC welder which would create square wave ac. This would be in the ball park of 20V 130A 60hz. My idea is to use solid state relays to flip the polarity of ...
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Control voltage required to turn on the LED through an NPN
simulate this circuit – Schematic created using CircuitLab
For this circuit, I am trying to figure out the value of \$V_1\$ DC which will turn on the LED, D1.
Since the forward voltage drop of ...
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BLDC controller
I have to design a controller for three phase BLDC motor. In BLDC motor, for each hall sensor signal combination we have to to energize two sets of stator phases. But how to correctly identify which ...
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How can I identify transistors with a low Vce-sat (collector-emitter saturation voltage)?
I want minimum voltage drop between collector and emitter as I have very small Vcc voltage to supply the load.
My Vcc is 3.3 volts. I want to use this switch to turn on/off 3 LEDs connected in ...
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LTC4440 boosting in LTSpice, but not in reality
I have a simple LTC4440-5 circuit in both LTSpice:
(R1 is just a load resistor, which isn't present in reality)
And here in the matrix, there's:
And:
(Note that a few parts are slightly different ...
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Input formula for 2 switching sine-waves (Heaviside eq'n)?
If we have 2 signal generators
1: \$\ 2sin(2 \omega t)\$
2: \$\ 3sin(5 \omega t)\$
being input to a selector switch that switches between the two continuous inputs every 0.5 seconds being sent to a ...
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half bridge IGBT not switching high side on
I have designed a PCB with a FAN73933 half bridge driver. It is designed to drive 2 IGBTs (FGH40N60SMD) with +- 170V rails. I have attached a schematic for better understanding. The problem is I can ...
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Power supply 5V
I need some help about choosing the best on board switching power supply that has the less electrical noise and longer life time between these schematics for a 5V 200mA board...
Heating is important ...
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Triac flickers when I apply main power
I am building an ESP32-based AC mains power switch by using TRIAC BT136-600D (common triac).
My first issue is my load didn't turn off the load (lamp) properly at 30%-40% brightness, and when triac ...
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Practical Considerations for a Square-Wave Inverter [closed]
I'm hoping to understand some practical considerations for a square wave inverter.
Particularly, is there additional circuitry I need around the transistors to ensure proper operation? (e.g., ...
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Switching a single high-power DC source between six loads - via relays?
I need to route DC power from a single rack power supply (Keysight N5766A) to six different loads, with the capability of switching between them independently and unshorted (break-before-make) via a ...
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Fast RF switching (Q-switching)
First question so feel free to ask for additional info if something is unclear. Quite a green EE that is very new to RF applications.
To provide some background: I am working on improving a substance ...
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Use a FET to switch 60 A LED current by microcontroller without voltage drop?
The project is a LED light bar consisting of:
20x Li Ion 21700 batteries in parallel (3.5 ... 4.2 V, 100 Ah) as power source (direct without any step up or step down converter),
1600 LEDs (...
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Inrush NTC thermistor vs. frequent on/off
NTC thermistors has high resistance at normal temperature, thus limiting the effect of a surge of current during power-up. Its resistance lowers after itself heating up during normal operation, ...
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Problems of optimal commutation depending on number of pole
I am trying to design a three phase 4 pole motor, control with six-step. My problem appears when I draw the commutation to try to see how everything work. First, with a basic three phase 2 pole, there ...
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VGA video switching using TS5v522
I am trying to bring video card signal to switch to a single monitor. I was hoping to use the TS5v522c but am not having much success. Data sheet below.
https://www.ti.com/lit/ds/symlink/ts5v522c.pdf#...
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MOSFET switch in 120 V AC application with Arduino Uno
I am working on a project that requires an Arduino Uno to activate a safety mechanism using 120 V AC from a power supply.
Is the following diagram correct, and are there items (such as a buffer/...
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ESP8266 deep sleep with external wakeup from 2 different GPIO
I'm trying to create a sensor that checks if the mailbox got new mail and when its emptied (it has 2 diffrent slots)
Is it possible to wake up an ESP8266 and checking which of the microswitches are ...
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Adding PWM option to continuous wave laser driver
I've been struggling for a few weeks now trying to add a PWM option to my CW laser diode driver design which works OK.
When adding a MOSFET or BJT to PWM the output, I'm getting voltage spikes and ...
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ESD Protection for LED
I have a main board with microcontroller and two long distance panel boards with standard 5mm red LEDs with 3.3k resistors. I supply panel boards with 24V over 20m cable. Whole system power is ...
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Reduce switching noise on autotransformer
I am trying to achieve the same thing they are talking about in this post, which is controling an autotransformer via software. I accidently even got the exact same autotransformer, but instead of a ...
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TRIAC driver circuit behavior when switching low current loads
I'm doing a project that involves switching different kinds of loads (edit: by that I mean loads that go from just a couple mA, up to 5A or so) using the usual TRIAC + opto-isolator combo (in my case, ...
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Switching between power sources with microcontroller
I need a way to switch a load(a high power LED) between two different power sources(50v and 100v) using a logic signal, quickly(<500us) and repeatably. I was going to use an n-channel high side ...
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Making aysnchronous sequential circuits hazard free
The problem I am stuck with requires me design a hazard free asynchronous sequential circuit for a given problem description. I have followed the routine steps as follows:
I have obtained the ...
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Can I use an optocoupler to switch an analog signal?
I have this setup to select 1 of 4 signals, pass it through a sensor, then output it to its own output line. It must also maintain all the signals at the output at all times, using optocouplers as ...
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Inconsistent Output Voltage in DC-DC Buck Converter
I'm trying to implement the following tps54302 DC-DC buck converter, for a 5V 3A output:
All resistor values 1% tolerance, capacitors 5% tolerance, inductor 20% tolerance.
I'm testing with a bench ...
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Measuring battery voltage, capacitor on drain (nMOSFET switching load)
I've got a schematic to measure a battery voltage using a nMosfet (triggered by a GPIO high level). The voltage is measured at the Probe (see picture).
Can you tell me the purpose of Capacitor C1 on ...
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Reducing ground level fluctuations when Multiplexing 7-Segment Displays
I am using a microcontroller to multiplex 6x 7-segment displays. Segments are driven by 2N3906’s and displays by a ULN2003. Average segment current is around 9mA, so instantaneous LED current pulses ...
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Is there any 'switching IC' to replace 'transistor switch' for switching the 12 volts LED array? [closed]
I have created a 12 volts LED array, and used a MOSFET to switch this panel. Do we have any switching IC which can switch it instead?
I will have five LED panels similar like this to switch at the ...
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power supply with Battery Backup -MOSFET reverse polarity does not work as intended
simulate this circuit – Schematic created using CircuitLab
This is my battery backup system for a laptop pc running 24/7.
So normally the Load is powered from primary supply and the battery is ...
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How to calculate the MOSFET switching time?
I am generating high voltage negative pulses using N-MOS.
Switching rate is 150 ns (6.67 MHz). Can I use IRF830 for 6.67 MHz switching?
How can I calculate the switching time of N-MOS?
i am getting ...
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Cascade of 555 timer with Control Voltage not triggering
Hi
I'm currently working on a cascade 555 circuit, both operating in the monostable mode. I also want to be able to control the pulse width with a voltage so am using applying 0-5v to the ctrl pin (...
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Slew Rate Adjustability
A SPST switch connects HB1 and HB2, to control a lamp connected to HB OUT. I am looking into modifying this circuit to make the slew rate adjustable when switching the output to VCC (around 12V). I ...
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Why not use actual switches instead of Relays
Relays are expensive and have limited lifetime. Choosing a proper relay for a particular application is also important. In other words relays require a bit more of everything when compared to a simple ...
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Transistor switching
I am using transistor as a switch, But am having a slight confusion. I am using the diagram below where I am using a 10ohm resistor. As I start switching the transistor instead of going into ...
user340506
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Does a TIP120 transistor have an internal resistance when switched on?
I'm having an issue with a TIP120 I'm using limiting current flowing through it.
I'm using the TIP120 to switch on/off a 12 V electromagnet. The circuit is working, but it appears the TIP120 is ...
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Function of this diode in this circuit
The following diagram is of a power switching driver...the transistor is a switching transistor which drives load that requires to on and off ....
Can anyone tell me what exactly is the function of ...
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