Hello there! This is my first time publicly asking for assistance with an electronic project of mine since I usually find all the answers I need somewhere online. However, this circuit has tested me past the point of breaking and I'm out of my depth (which is sad considering how simple the circuit is).
I am building a simple Power-Off delay circuit for the extension cable connected to all my TV's peripherals (not the TV itself). The USB port of my TV only receives power when the TV is turned on, that's where I started. I wanted my circuit to switch a relay powering the extension cord connected to all of my equipment (PS4, Xbox, Speakers, ChromeCast). I found this helpful diagram online, but it relies on the power source remaining present after the switch is opened. I then thought of using the power of a USB Wall Wart to temporarily power the circuit (and extension cord) for around 10 minutes after the TV's USB lost power.
After countless different designs and much trial and error I thought I had a circuit that would do the job, but when I put it all together (and tested it again to make sure all was well) and plugged it all in, it didn't work; the diodes got really hot so I unplugged everything. I would really prefer not to have to use a 555 timer for this project, but we'll see. I've seen countless other projects that use a single power supply to run the circuit for a short time after a switch is opened, but I haven't seen one that encompasses the use of 2 power supplies (one to first engage the relay and the second to keep it on for 10 minutes after the first power supply is gone).
I understand there are products I can buy online that use extension cords with the ability to turn off connected devices when the control device turns off, but I wanted to build in a delay timer to avoid having the TV accidentally turn off and kill the power to the console when I'm playing a game.
I don't have any nice circuit design software, so I substituted an 8 pin IC for the relay I am using. This is the relay I bought:
http://www.ebay.com/itm/5V-Two-2-Ch...509345?hash=item2a26055221:g:aVcAAOSw0e9UvczK
In my diagram pin 1 is Vcc, pin 2 is the control (In 1) and pin 4 is GND. I'm using very cheap transistors I got on ebay, and same with the diodes. After many test it almost seems as if the resistor has no influence on the delay of the circuit power-off: it's primarily based on the capacitor's value. The 47uF capacitor I'm using delays the power-off by around 13 minutes.
Could it be I have made the circuit to "simple" and there is not enough resistance to reduce the current drawn from the TV and therefor the diodes overheat? I'm confident my soldering is fine since my tests of the circuit with my arduino were fine.
Again, I'm not very experienced with electronics, I just have a working knowledge of very basis properties of components. I would really appreciate some assistance or advice on how to proceed. Thank you so much.
I am building a simple Power-Off delay circuit for the extension cable connected to all my TV's peripherals (not the TV itself). The USB port of my TV only receives power when the TV is turned on, that's where I started. I wanted my circuit to switch a relay powering the extension cord connected to all of my equipment (PS4, Xbox, Speakers, ChromeCast). I found this helpful diagram online, but it relies on the power source remaining present after the switch is opened. I then thought of using the power of a USB Wall Wart to temporarily power the circuit (and extension cord) for around 10 minutes after the TV's USB lost power.
After countless different designs and much trial and error I thought I had a circuit that would do the job, but when I put it all together (and tested it again to make sure all was well) and plugged it all in, it didn't work; the diodes got really hot so I unplugged everything. I would really prefer not to have to use a 555 timer for this project, but we'll see. I've seen countless other projects that use a single power supply to run the circuit for a short time after a switch is opened, but I haven't seen one that encompasses the use of 2 power supplies (one to first engage the relay and the second to keep it on for 10 minutes after the first power supply is gone).
I understand there are products I can buy online that use extension cords with the ability to turn off connected devices when the control device turns off, but I wanted to build in a delay timer to avoid having the TV accidentally turn off and kill the power to the console when I'm playing a game.
I don't have any nice circuit design software, so I substituted an 8 pin IC for the relay I am using. This is the relay I bought:
http://www.ebay.com/itm/5V-Two-2-Ch...509345?hash=item2a26055221:g:aVcAAOSw0e9UvczK
In my diagram pin 1 is Vcc, pin 2 is the control (In 1) and pin 4 is GND. I'm using very cheap transistors I got on ebay, and same with the diodes. After many test it almost seems as if the resistor has no influence on the delay of the circuit power-off: it's primarily based on the capacitor's value. The 47uF capacitor I'm using delays the power-off by around 13 minutes.
Could it be I have made the circuit to "simple" and there is not enough resistance to reduce the current drawn from the TV and therefor the diodes overheat? I'm confident my soldering is fine since my tests of the circuit with my arduino were fine.
Again, I'm not very experienced with electronics, I just have a working knowledge of very basis properties of components. I would really appreciate some assistance or advice on how to proceed. Thank you so much.
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