Questions tagged [switches]

Devices to interrupt or route a signal or power one of several ways.

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2answers
21 views

How can I switch multiple lines using a single switch?

I am looking to make a switchbox for my 34 pin floppy drive (I know you can't hotswap) but I don't know what to use. I have heard of a multiplexer but I think it is only one way. I need to be able to ...
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0answers
20 views

Intercom re-wiring to open door on bell pushed [on hold]

I have a normal old intercom system in my appartement building pick up the horn, can talk 2 ways at the same time. Button to push for the door to open. Now what i want to do is whenever someone rings ...
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0answers
14 views

Device to switch between two light with a single wall switch [migrated]

first of all, sorry about to be asking that silly and newby question, I know, it is really lame. Is there a simple device, that I can build simply, or bought, that can switch between two lights ? I ...
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0answers
26 views

How to use analog switch to create a USB switch [on hold]

I have 2 PCs with one monitor, I want to sometimes switch from one to another, the only things are the keyboard and mouse, i have to have 2 keyboards and 2 mouses for two computer. I want to have a ...
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1answer
405 views

Op Amp as a simple switch

I want to build a little voltage switch that switches on a buzzer and a relay when a certain voltage is reached. Please have a look at the schematic. I use a trim potentiometer to set up the switch ...
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0answers
41 views

Improving effciency in medical implant with load switching

I'm trying to design and simulate the Q-modulation technique for a body implant. The technique involves two loops: one outside the body, with resonating LC tank producing a big voltage. Another loop ...
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1answer
42 views

NC button to supply +12V to solenoid

I've got a normally closed momentary push button switch that I would like to make behave as normally open. E.g. I press the button and 12V is supplied to the solenoid. I understand that it would be ...
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1answer
24 views

Led Strip switches

Good day everyone. I am not a pro electrician, I am just a student who wants something new in our house. I hope that you can help me with this. And this will be much appreciated. I want to put led ...
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2answers
141 views

Where are all the multiplexers?

I am trying to implement a circuit where 2 SPI drives (basically two masters) speak to 1 slave. Both operate on a 3 wire SPI. Keeping that in mind I was going to have the CLK and MOSI of both as ...
3
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2answers
254 views

Two logic circuits controlled from two SPST switches?

I have two low power 12 volt circuits (C1, C2) that operate relays. I want to control these with two SPST switches (S1, S2) in a Boolean manner: (S1 OR S2) for C1, and (NOT S2) for C2. Can these ...
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1answer
136 views

PWM controller circuit Issue

I'm having an issue with this PWM controller circuit. In this circuit the potentiometer comes with a on/off switch. The way it should work is: As the potentiometer resistance value varies the output ...
4
votes
1answer
168 views

Induced power supply noise on switch contact

I have a circuit that has a 24V section and a 5V section, separated by opto-isolators and an isolated DCDC converter. Both sides of the DC-DC have decoupling caps, and the MCU has one per Vcc pin. ...
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1answer
40 views

Can an I2C switch control multiple I2C switches?

I was wondering if I am able to treat an I2C switch simply as another I2C device and use 1 switch to control more switches downstream. This picture below shows what I am trying to do.
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1answer
80 views

Arduino controlled switch for 8V 5A

So, my problem is very simple: I need to use an Arduino to control whether or not my circuit is open or not. However, I need a low resistance (less than 1 Ohm, hopefully) switch (Relay, Transistor, ...
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1answer
35 views

DPDT Switch Microcontroller

Is there a microcontroller equivalent of a DPDT Switch? I am trying to develop a product that requires remote reversal of polarity by incorporation some sort of an equivalent of the mechanism ...
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0answers
46 views

Help Wiring An NVR Switch [closed]

Some one has replaced The solenoid switch & made a hash of the wiring. Im Not good with wiring diagrams so hopefully the information on the picture will help.? This is from a Inca bandsaw. enter ...
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1answer
93 views

Find the transfer function of the circuit if current I is the measured output

So there's this problem I am trying to solve: Consider a series RL circuit corrected to a DC voltage source and an on-off switch. Assume R = 2 ohms, and L = 1H, and applied voltage V = 10 volts. ...
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2answers
130 views

Proximity Sensor Switch Circuit

My goal is to build a proximity sensor switch circuit that can turn an LED on OR off. If I wave my hand, the light will turn on. Similarly, the light will turn off if I wave my hand the second time. I ...
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1answer
191 views

How to analyze RL circuit with sequential switching?

I am trying to solve this question: However, I am having difficulties solving as I only have come across circuits which are initially closed then opened, not vice versa as is the case here. ...
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1answer
60 views

Two state switch using transistor (bi-directional)

I have an existing pair of wires driving a servo motor. One of them is +12V, the other one 0V. Depending on the rotation direction of the motor, the voltage flips. I now want to put an optional ...
0
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1answer
152 views

Latching power circuit with short-to-ground switch

I'm trying to build a circuit around an existing switch that allows another component to override the switch state. (Our component is a computer and the feature we're trying to build is remote-...
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0answers
29 views

Protecting back to back mosfets

I'm designing a high side back to back common source bidirectinal power switch made from n-mosfets. schema: Schematic attached. The questions: How can i protect driver from voltage spike from ...
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1answer
91 views

Switch a 12 VDC circuit from a 0.6 volt signal

I need to switch a 12 VDC circuit (automotive ignition coil) with a .6vdc signal from an impulse coil. I am trying to replace the ignitor box for this engine; they are extraordinarily expensive and ...
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1answer
98 views

Bypassing refrigerator door alarm piezoelectric buzzer

My appliances keep beeping at me. How can I deactivate or bypass this refrigerator door alarm buzzer without affecting the rest of the circuit? I thought I could just cut/connect the wires at the ...
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1answer
142 views

Finding total energy for RC discharged capacitor at t = ∞?

Most Rc circuits are not as severely difficult as this kind of circuit. I'm trying to solve for both the time constant and the voltage V2 across the R2 resistor, both of which will hold the necessary ...
0
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1answer
31 views

Voltage comparison circuit (Voltage level operated switch)

I am trying to implement a voltage level detection circuit for e.g. I have 60V power supply and I need to check that if the input voltage is 1.5V or higher to turn on DC/DC or just high signal so I ...
2
votes
2answers
97 views

Electrically toggle-able switch?

I'm wondering if a switch exists that fits this functionality I imagine: The user would depress the switch, it would latch and stay depressed. Once the product completes its function, the control ...
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1answer
163 views

Simulink “ideal switch” block changes output unexpectedly

I am attempting to simulate a DC motor circuit on Simulink. I have built the block diagram mainly according to a tutorial, and am confused about an aspect of it. The main circuit has a DC power source ...
6
votes
3answers
5k views

Using MOSFET to switch device

Will my circuit work for the following goal? When INPUT_N is HIGH (i.e. micro is not driving it and it is pulled up to 3.3V), VCC pin on device will have 24V. When the microcontroller drives INPUT_N ...
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4answers
90 views

Is it possible to use a DPDT switch to swap 2 inputs and 2 outputs?

I want to create a passive device with two MIDI inputs and two MIDI outputs, with a switch that has two states. In the first state, input 1 is connected to output 1, and input 2 is connected to output ...
0
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2answers
221 views

Options to read an 8x8 switch matrix?

I have a project (pinball machine) that will have a decent number of microswitches that will be connected in an 8x8 switch matrix. I'm trying to determine what my options are for reading this matrix ...
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0answers
51 views

Switch DC/DC Converter through Fiber Optic Signal

I need to send a signal through fiber optic to switch a DC/DC Converter (I want it to be on when there is photocurrent, and off when there isn't), I can't use a normal cable because I want to do that ...
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3answers
179 views

RC / Airsoft Battery Switch [On-Off-On]

Morning all, I am toying with the idea of wiring up a small On-Off-On rocker switch which will control which battery will be active in my Airsoft setup. Below is a brief diagram of how I expect this ...
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1answer
286 views

IGBT contactor design

I found this circuit in an older post. I was thinking about using this in place of a contactor to break under load. The load would be at 500V 300A DC. There would be overcurrent protection in line ...
2
votes
4answers
409 views

N-Channel Mosfet as Switch

I have a few n-channel MOSFETs (the irlb8721's) and I was able to use it as a switch to control an led with the gate at 5 volts. I would like to change the source/drain voltage to 11.1v from 5v and ...
0
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1answer
90 views

Autodetection of presence of internal CT burden on plug-in CT

I am going to measure 3 phase energy using CT from YHDC model SCT013-000 (100A:50mA) and SCT013-100 (100A:1V). I have a board which is done in my company and my job this moment is make a shield board ...
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2answers
46 views

How to make a circuit to pulse an output when a momentary switch is released

I need to make a circuit that has a momentary switch and a light (30mW). When the switch is pressed, nothing should happen, but when the switch is released, I want it to pulse the light for a short ...
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1answer
37 views

What is the difference between 3 and 4 Pin IEC320 C14 Power Sockets?

What is the difference between 3 and 4 Pin IEC320 C14 Power Sockets? Looking at the picture attached from reseller I cannot see what the 4th pin serves and I cannot find a description anywhere short ...
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2answers
68 views

Working on a design that requires a specific kind of physical switch [closed]

The switch my design needs behaves like the picture below. The user would slide the switch to the right to activate it and the switch would return to the left automatically, I assume by some kind of ...
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2answers
221 views

electronic switch, understanding on-resistance measurements

I'm trying to understand from the datasheet, how much on-resistance I will get from this electronic switch: DG411 datasheet: https://datasheets.maximintegrated.com/en/ds/DG411-DG413.pdf given this ...
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3answers
129 views

How to wire a 4PDT Switch to switch Rs and Caps for Hi/Lowpass filter Sallen Key Equal Component

I'm making an active Low/High Pass filter based on the equal component sallen key design I found in the Active Filter Cookbook. In the book I read that by exchanging the position of the Frequency ...
0
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1answer
84 views

Does anyone know what these marine radio pot/switches are or what they do?

I enjoy re-purposing misc items and components to make neat gadgets etc. I have salvaged these two "switches" from an old marine radio. The rods on each click in and click out and rotate in both ...
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2answers
198 views

high side MOSFET switch and BJT interface with MCU GPIO

im operating a 28V contactor using a GPIO from my MCU, i have a 28V supply readily available. im looking to surpass the gate threshold of the MOSFET by introducing a NPN BJT with a 10V supply, with ...
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votes
1answer
109 views

What is this white component? [duplicate]

Anybody knows what this component is? (The white cylinder.) It has to be some kind of switch since it is marked as "S2", but I never saw anything like it before. Thanks!
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0answers
20 views

Issues due to sudden load disconnection/connection

I am working on a circuit (schematic enclosed) which is being powered by a high discharge LiSOCl2 battery. A TPS61232 based 5V booster powers two loads: LOAD1 is directly connected to the 5V bus ...
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0answers
25 views

What is the best way to isolate power hold-up circuit?

I an currently designing a hold up circuit for a computer and I need to keep this load isolated from other circuits that don't need to worry about a brief loss of power. The research I've done has ...
4
votes
4answers
775 views

Is a protection diode needed for a resistive load?

In some applications a flyback diode is added parallel to the load. Is that because the switching causes reverse voltage for inductive loads? What if we have a resistive load instead? Do we still need ...
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1answer
182 views

Hamlin Reed Relays for Audio: Sink or Source?

I'm building a small stripboard audio switchbox using some hamlin 5v reed relays (HE3621A0550, mouser link here). A small SPST momentary switch activates the relay. Wondering if the best practice is ...
0
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1answer
48 views

Where should I put my switch - on the enable of my SMPS or the power input?

I'm designing a simple board with a FitiPower FP6717 step-up converter chip (Datasheet) and a mechanical switch (SPDT) to enable or disable the output power. My design for the boost will be very close ...
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1answer
215 views

Switch/Pushbutton for Multiple LED String Lights

I'm helping my daughter with a science project. We're designing a glove for crossing guards with red and green LEDs attached. I thought it would be a good idea to put a small button in the thumb area ...