Questions tagged [switches]
Devices to interrupt or route a signal or power one of several ways.
1
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2answers
70 views
Switching of RS485 differential line. Two sources, one output
I'm looking for a solution for my project.
I have two signal sources (primary source and secondary source) on the RS485 (A/B) differential line. When/if something goes wrong on the primary, then I ...
0
votes
0answers
32 views
On off slider switch
On the above board there was a slider switch that was faulty, if I wanted to test this without the switch and short it where do I connect 2 to c, the c to the right of 2. Do I also need to jump on pad ...
0
votes
1answer
20 views
getting arduino PWM from 0-5V to 0-10V or 0-12V?
I have an IR2110 driver and a LOD voltage regulator 15V from a solar panel. now this will supply 15V to VCC as shown below. Since I have a LOD voltage regulator of 15V, I can't apply the same voltage ...
0
votes
2answers
53 views
How to create a switch that when pressed opens, but after a time delay returns to the original state?
I am creating a buzzer driver that turns on when the output of an AND gate goes HIGH. What I would like to create is some way to shut off the signal to the buzzer by opening an SPST switch, but the ...
0
votes
2answers
57 views
Devices with temporary push-on,push-off switches?
I have a couple of china-cheapie devices that seem to use some circuit with a single button where first push turns it on, second turns it off -- e.g. the button works as a toggle.
I would prefer to ...
0
votes
1answer
53 views
How does voltage/current limits work in switches?
I want to get a rotary switch, it says that it can handle 600 V and 40 A. I will use it to turn ON two DC brushed motors of 12 V 20 A. So, the voltage is way too high but the current is just right.
...
0
votes
1answer
23 views
touch switch time problem
I was looking for a way to make a touch touch switch and i found this circuit on the internet but the problem is , it goes off automatically after few seconds
is there any way that i can control it ...
1
vote
2answers
54 views
Using transistor as switch in the “middle” of the circuit
I have an rather complex circuit with button micro-switch in the middle (actually, it's RF remote control with 3 buttons).
I would like to be able to simulate the micro-switch click on it with one of ...
0
votes
1answer
41 views
Pre charge resistor switch
I have a 12V 40A motor. I have a switch between the motor controller and the battery.
I want to put a pre charge resistor in the path. Like in the figure.
My questions are:
1) The pre charge ...
3
votes
1answer
71 views
Switch between 2 power supply feeds without device losing power
I have done a search on here but didn't find the answer (maybe "woods for the trees") but here goes...
A brief 'background' -- In my house, there's a switch by my front door that turns on/off the ...
1
vote
2answers
79 views
How to make momentary connection on power on?
I have a mini-computer Beelink AP34 with momentary power button and I need to simulate short pressing of this button once it is connected to the power (12V DC).
The reason is that it doesn't start ...
0
votes
2answers
35 views
Triac switch cause of heating
As a newbie to hardware design, I'm having some trouble picking components. I want to switch a 24V AC Solenoid valve using a triac.
According to my research/experience, transistors heat up during use. ...
0
votes
0answers
35 views
How to create switch that changes from HIGH to LOW states when receiving a HIGH signal?
I’m creating a circuit and one of the controls is a tactile SPST switch where the common is connected to VDD. What I’m trying to do is to have some SPDT where its common is connected to a multiplexer’...
2
votes
1answer
42 views
Design of a motor SPDT switch that can be triggered by 5 V or 3.3 V digital output
Problem:
I am designing the electrical system for a vehicle that has 12 brushed dc motors / linear actuators, they are driven by 6 identical dual-channel motor driver boards, that provide a maximum ...
0
votes
1answer
31 views
Reverse function optocoupler in series with physical NC switch?
I've read this answer
(reverse function optocoupler) but my case is different:
I've got a CNC mini lathe.
I have a limit switch on one of the lathe's axis ends (X+) wired as NC to my Gecko G540 ...
0
votes
0answers
11 views
Light and fan switches [migrated]
I would like to have a double wall switch for the toilet where one switch (#1) turns on both the light and the fan while the second switch (#2) turns only the fan. Please note the light and the fan ...
1
vote
3answers
88 views
Why Does this Short? [closed]
simulate this circuit – Schematic created using CircuitLab
I'm new to electronics and wired a dc motor to a battery and switch. After the battery got really hot, I realized that it was probably ...
1
vote
0answers
31 views
Can't find replacement for switch
I am trying to repair a nespresso machine(not a job, just for fun) and the PCB had the following switch:
I tried to google it as "switch", "switch 4 pin", "1552", but nothing returned a switch ...
0
votes
1answer
57 views
NPN transistor won't saturate when Vcc is greater than 7 volts
Am I missing something here?
I have an NPN transistor (2N2222) with a 10K resistor from collector to Vcc.
Also a 10K resistor from base to input signal. Emitter is grounded.
The base input is ...
0
votes
1answer
36 views
Relay or Transistor as low DC switch
I am working on a project for a watering controller where I would need to turn on or off an solenoid valve (electric valve), my first thought would be to use a relay, but I know relays are good for ...
0
votes
1answer
37 views
How to bypass minimal load limitation on a power switch?
I got a power switch which seems to have minimal load that makes it incompatible with LED lights.
Schneider GUPA1411BSS 1 Gang 1 Way PIR Switch — after unpacking I found it has only L, L1 and earth ...
1
vote
2answers
68 views
Need to turn on a relay for half a second when constant power is applied with a switch
I'm looking for what circuit I'd need using basic components to do this task.
Essentially I have a switch that turns on two relays, one of which needs to be on as long as the switch is depressed, but ...
19
votes
5answers
5k views
Why can't I see bouncing of a switch on an oscilloscope?
I'm trying to view the bouncing of a simple switch on an oscilloscope.
I have prepared a simple breadboard circuit (power → switch → resistor → ground). The problem is, it is displayed as a perfect ...
1
vote
0answers
32 views
Push and hold on/off switch for arduino [migrated]
Many electronic devices turn on/off, or more correctly on/sleep, by pressing a button and holding it for two or three seconds. I would like to put this ability into a project using an Adafruit Feather ...
0
votes
1answer
54 views
buck converter with a simple bypass schematic mode?
in my design i need to place a buck converter 10-30V input with a fixed 12V output. my concern is that when the battery volatge level is low (for instance 10v) the device will stop bucking. so i want ...
0
votes
1answer
46 views
BJT switches pair
simulate this circuit – Schematic created using CircuitLab
I'm trying to do something like this: V1 is a variable (0 to 3.3V) voltage source, so above some value like 0.7 ~ 1.0 V I want Q1 as a ...
0
votes
1answer
75 views
Switching circuit
I am making a switching circuit with two input sources A and B of 5 volts each and one or more outputs C1, C2, C3 etc.
Source A is constant and source B is variable, has two states on and of.
Source B ...
0
votes
3answers
48 views
How to debounce a low pulse switch for automotive lighting
Hoping you guys can give me a hand with some wiring that I can't quite figure out!
Background: I'm trying to rewire a set of automotive lights - these are normally controlled by a computer but I'm ...
2
votes
2answers
49 views
Switches for current source
simulate this circuit – Schematic created using CircuitLab
I1 is an wilson modified current source by 4 pnp transistors. SW1 and SW2 are doubts. When SW1 is open, SW2 must be closed and vice ...
0
votes
1answer
78 views
“Normally closed” switch with NPN transistors
Is it possible to have "Normally closed" switch with NPN transistor when the voltage at the base is 0V? So far I only managed to achieve this result with NPN transistor when the base is HIGH. When the ...
0
votes
0answers
45 views
Raspberry Pi GPIO output not working with MOSFET N Channel Switch
My circuit is below - I'm trying to switch a solenoid valve using a Raspberry Pi.
I have tested the MOSFET switch with the dedicated 3v3 pin on the Raspberry Pi, and have also tested that GPIO pin ...
-2
votes
2answers
55 views
what is the right power supply switch for a sensor?
i'm trying to control my sensors power supply to reduce the current consumption of my project.
i'm using ATmega328p that collect information from different sensors (digital and analog sensor) and send ...
1
vote
3answers
58 views
High side Mosfet switch leakage issue?
Wasn't sure how to headline this but here it is:
I'm debugging one of my coin cell ON/OFF switch. Circuit is as follows:
simulate this circuit – Schematic created using CircuitLab
Basically a ...
2
votes
1answer
58 views
Using two momentary switches to toggle LED
So, this circuit should (in theory, at least) turn the diode on when ON button is pressed, and turn it off when OFF button is pressed. It doesn't though. The diode is powered on at the moment where I ...
1
vote
0answers
32 views
L298N motor driver not working after connecting SPST switch
So when I had all wired as depicted in the first image, it worked fine, no problems. The red LED on the L298N board was illuminated and the dc motor was following commands from my Raspberry Pi.
Now I ...
0
votes
2answers
31 views
Two 12v 1A DC power sources using a 1 gang switch?
I'm wondering if it is possible to connect two 12v 1A DC power sources to a single switch? And if so, how would such a schematic look like. The two power sources will then power their own things.
3
votes
2answers
123 views
dpdt switch to spst switch
I am trying to build a raspberry pi gameboy emulator with a custom board inside of a gameboy adv sp shell. I decided to use an open-source board made by some guy on the internet and I will be ...
1
vote
1answer
35 views
Automatic transfer switch or some such solution
I have only rudimentary knowledge of electronics.
I live in South Africa, where we are now experiencing rolling blackouts. (Euphemistically called "Load Shedding" here.) During the day it's just a ...
0
votes
1answer
48 views
Switch for low voltage, high current Shape Memory wire
I need a switch to allow current to pass through a wire to Joule heat it. This is a nickel-titanium wire (Shape Memory Alloy, SMA) which has been programmed to bend into a particular shape when heated....
0
votes
1answer
65 views
Single key not working on DIY mechanical keyboard (xd75re PCB and Switch both work)
I have assembled my first mechanical keyboard using the xd75re PCB. I used a plate mount, and all of the switches were installed without issue (this PCB has hotswap). When I used keyboardtester.com to ...
0
votes
2answers
68 views
What type of switch is this push switch [photos]?
I suspect this switch isn’t functioning correctly and would like to replace it but can’t find one similar. What sort of switch is it?
The front is a push with two states (in/out) and has a bulb to ...
0
votes
1answer
50 views
Smart Wi-Fi Switch with No Ground
I want to install some smart switches in an older home without ground wires.
I'd also prefer not having to purchase a "Smart Hub" as they seem to be going away and not necessary.
Note, I use Google, ...
4
votes
1answer
100 views
How do I assemble the mechanical parts of panel mount switch? (lock ring, lock washer, nut, etc)
I'm sure this is a very simple question, but I'm not familiar with the different mechanical parts of a simple switch.
For example, I've purchased this switch and it includes:
Switch
"Lockwasher" ("...
0
votes
4answers
61 views
4.5 V on gate of Mosfet while switch open
I have a strange behavior with the circuit below.
(the bidirectional logica level should be read as:
VL = Voltage Low
GNDL = GND Low
VH = Voltage High
GNDH = GND High
L1 = Low channel 1 (I did only ...
-1
votes
3answers
61 views
Help with making sure a correct use of a BJT
I'm designing a PCB that receives 3 power inputs 3.3v, 5v and 12v.
I need simple way to switch all of them of in one go.
Here is a schematic of my PCB
My 12V line is for running a ws2815 led strip ...
0
votes
1answer
49 views
Latching switch to single pulse circuit? (monostable multivibrator with 555?)
I am looking at using a latching switch (SPDT) to momentarily connect two pins. This is for a power button for a raspberry pi, so to power the machine from a hold state you have to momentarily short ...
1
vote
0answers
65 views
switch without diode
I have a project where I need to put a switch in between the resource from tester and the DUT.
My DUT is a 48 pin device (semiconductor IC), each of the pins has its own ESD diode. The switch, for ...
0
votes
3answers
113 views
Why is my crystal oscillator not working with KSZ8999 switch?
I am using KSZ8999 ethernet switch from Micrel and I have problem with 25 MHz external oscillator. There is constant 2,1 VDC on output pin which is VDD for the switch, so crystal is not oscillating.
...
0
votes
3answers
63 views
Question regarding ground when using teensy to control a mosfet switch
Despite the fact that I'm pretty new to electronics I'm working on a quite ambitious project which is basically a USB-Midi Controller attached to different devices that send different signals. The ...
0
votes
4answers
117 views
Can an optocoupler be used as a switch [closed]
I am trying to replace a analog switch (the switch is a momentary button in a low current DC situation) with optocoupler.
Is it possible to use an optocoupler as a switch (i.e. just on/off)?
...
