Two LEDs using, probable problem?
I use a simple circuit to notify user the reverse biased voltage to prevent some issues.
Vcc can be -18~+18V, and two LEDs have exactly same reverse voltage (5V), but they have different forward voltage (because their LED wavelengths are different, blue one has 3V, red one has 1.8V). Will this setting cause a problem? In my test this circuit not failed but I'm not convinced. I think if the LED voltage is within the range of the reverse voltage, it's just okay. Is my thought right?
led diodes
edited 2 hours ago
winny
4,49431828
asked 9 hours ago
Chanho Jeon
153
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Chanho Jeon is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
I use a simple circuit to notify user the reverse biased voltage to prevent some issues.
Vcc can be -18~+18V, and two LEDs have exactly same reverse voltage (5V), but they have different forward voltage (because their LED wavelengths are different, blue one has 3V, red one has 1.8V). Will this setting cause a problem? In my test this circuit not failed but I'm not convinced. I think if the LED voltage is within the range of the reverse voltage, it's just okay. Is my thought right?
led diodes
edited 2 hours ago
winny
4,49431828
asked 9 hours ago
Chanho Jeon
153
New contributor
Chanho Jeon is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
2
As long as the currents are not excessive, the two LEDs should protect each other from excessive reverse voltage.
– jonk
9 hours ago
Just don't decide to take one out momentarily... ie, this is better soldered up than on a breadboard.
– Chris Stratton
2 hours ago
add a comment |
I use a simple circuit to notify user the reverse biased voltage to prevent some issues.
Vcc can be -18~+18V, and two LEDs have exactly same reverse voltage (5V), but they have different forward voltage (because their LED wavelengths are different, blue one has 3V, red one has 1.8V). Will this setting cause a problem? In my test this circuit not failed but I'm not convinced. I think if the LED voltage is within the range of the reverse voltage, it's just okay. Is my thought right?
led diodes
edited 2 hours ago
winny
4,49431828
asked 9 hours ago
Chanho Jeon
153
New contributor
Chanho Jeon is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
I use a simple circuit to notify user the reverse biased voltage to prevent some issues.
Vcc can be -18~+18V, and two LEDs have exactly same reverse voltage (5V), but they have different forward voltage (because their LED wavelengths are different, blue one has 3V, red one has 1.8V). Will this setting cause a problem? In my test this circuit not failed but I'm not convinced. I think if the LED voltage is within the range of the reverse voltage, it's just okay. Is my thought right?
led diodes
led diodes
edited 2 hours ago
winny
4,49431828
asked 9 hours ago
Chanho Jeon
153
New contributor
Chanho Jeon is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 2 hours ago
winny
4,49431828
asked 9 hours ago
Chanho Jeon
153
New contributor
Chanho Jeon is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
edited 2 hours ago
winny
4,49431828
edited 2 hours ago
winny
4,49431828
edited 2 hours ago
winny
4,49431828
4,49431828
asked 9 hours ago
Chanho Jeon
153
New contributor
Chanho Jeon is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 9 hours ago
Chanho Jeon
153
asked 9 hours ago
Chanho Jeon
153
153
New contributor
Chanho Jeon is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Chanho Jeon is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Chanho Jeon is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
2
As long as the currents are not excessive, the two LEDs should protect each other from excessive reverse voltage.
– jonk
9 hours ago
Just don't decide to take one out momentarily... ie, this is better soldered up than on a breadboard.
– Chris Stratton
2 hours ago
add a comment |
2
As long as the currents are not excessive, the two LEDs should protect each other from excessive reverse voltage.
– jonk
9 hours ago
Just don't decide to take one out momentarily... ie, this is better soldered up than on a breadboard.
– Chris Stratton
2 hours ago
2
2
As long as the currents are not excessive, the two LEDs should protect each other from excessive reverse voltage.
– jonk
9 hours ago
As long as the currents are not excessive, the two LEDs should protect each other from excessive reverse voltage.
– jonk
9 hours ago
Just don't decide to take one out momentarily... ie, this is better soldered up than on a breadboard.
– Chris Stratton
2 hours ago
Just don't decide to take one out momentarily... ie, this is better soldered up than on a breadboard.
– Chris Stratton
2 hours ago
add a comment |
2 Answers
2
active
oldest
votes
Will this setting cause a problem?
No it will not.
I think if the LED voltage is within the range of the reverse voltage, it's just okay. Is my thought right?
Yes, you are right. As long as you are operating the LEDs within their safe limits, they will not be affected
There are some readily-available, multi-colour bi-directional LEDs on the market. Please follow this link: Led-link
edited 2 hours ago
TonyM
8,57811129
answered 9 hours ago
Satish Singupuram
7559
I hadn't heard about the bi-directional LEDs. Thank you.
– Chanho Jeon
9 hours ago
add a comment |
Because the two LEDs are back to back the maximum reverse voltage applied to one will be the forward voltage, Vf, of the other.
... blue one has 3 V, red one has 1.8 V ...
When the blue LED is lit there will be 3 V in reverse across the red and when the red is lit there will be 1.8 V in reverse across the blue. This is how the bi-directional LED is intended to be used and it will be fine.
As far as I remember, bi-directional LEDs are available with the same colour in both directions. These are suitable for AC indicators and eliminate the requirement for an external diode.
answered 8 hours ago
Transistor
80.2k778173
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
Will this setting cause a problem?
No it will not.
I think if the LED voltage is within the range of the reverse voltage, it's just okay. Is my thought right?
Yes, you are right. As long as you are operating the LEDs within their safe limits, they will not be affected
There are some readily-available, multi-colour bi-directional LEDs on the market. Please follow this link: Led-link
edited 2 hours ago
TonyM
8,57811129
answered 9 hours ago
Satish Singupuram
7559
I hadn't heard about the bi-directional LEDs. Thank you.
– Chanho Jeon
9 hours ago
add a comment |
Will this setting cause a problem?
No it will not.
I think if the LED voltage is within the range of the reverse voltage, it's just okay. Is my thought right?
Yes, you are right. As long as you are operating the LEDs within their safe limits, they will not be affected
There are some readily-available, multi-colour bi-directional LEDs on the market. Please follow this link: Led-link
edited 2 hours ago
TonyM
8,57811129
answered 9 hours ago
Satish Singupuram
7559
I hadn't heard about the bi-directional LEDs. Thank you.
– Chanho Jeon
9 hours ago
add a comment |
Will this setting cause a problem?
No it will not.
I think if the LED voltage is within the range of the reverse voltage, it's just okay. Is my thought right?
Yes, you are right. As long as you are operating the LEDs within their safe limits, they will not be affected
There are some readily-available, multi-colour bi-directional LEDs on the market. Please follow this link: Led-link
edited 2 hours ago
TonyM
8,57811129
answered 9 hours ago
Satish Singupuram
7559
Will this setting cause a problem?
No it will not.
I think if the LED voltage is within the range of the reverse voltage, it's just okay. Is my thought right?
Yes, you are right. As long as you are operating the LEDs within their safe limits, they will not be affected
There are some readily-available, multi-colour bi-directional LEDs on the market. Please follow this link: Led-link
edited 2 hours ago
TonyM
8,57811129
answered 9 hours ago
Satish Singupuram
7559
edited 2 hours ago
TonyM
8,57811129
edited 2 hours ago
TonyM
8,57811129
edited 2 hours ago
TonyM
8,57811129
8,57811129
answered 9 hours ago
Satish Singupuram
7559
answered 9 hours ago
Satish Singupuram
7559
answered 9 hours ago
Satish Singupuram
7559
7559
I hadn't heard about the bi-directional LEDs. Thank you.
– Chanho Jeon
9 hours ago
add a comment |
I hadn't heard about the bi-directional LEDs. Thank you.
– Chanho Jeon
9 hours ago
I hadn't heard about the bi-directional LEDs. Thank you.
– Chanho Jeon
9 hours ago
I hadn't heard about the bi-directional LEDs. Thank you.
– Chanho Jeon
9 hours ago
add a comment |
Because the two LEDs are back to back the maximum reverse voltage applied to one will be the forward voltage, Vf, of the other.
... blue one has 3 V, red one has 1.8 V ...
When the blue LED is lit there will be 3 V in reverse across the red and when the red is lit there will be 1.8 V in reverse across the blue. This is how the bi-directional LED is intended to be used and it will be fine.
As far as I remember, bi-directional LEDs are available with the same colour in both directions. These are suitable for AC indicators and eliminate the requirement for an external diode.
answered 8 hours ago
Transistor
80.2k778173
add a comment |
Because the two LEDs are back to back the maximum reverse voltage applied to one will be the forward voltage, Vf, of the other.
... blue one has 3 V, red one has 1.8 V ...
When the blue LED is lit there will be 3 V in reverse across the red and when the red is lit there will be 1.8 V in reverse across the blue. This is how the bi-directional LED is intended to be used and it will be fine.
As far as I remember, bi-directional LEDs are available with the same colour in both directions. These are suitable for AC indicators and eliminate the requirement for an external diode.
answered 8 hours ago
Transistor
80.2k778173
add a comment |
Because the two LEDs are back to back the maximum reverse voltage applied to one will be the forward voltage, Vf, of the other.
... blue one has 3 V, red one has 1.8 V ...
When the blue LED is lit there will be 3 V in reverse across the red and when the red is lit there will be 1.8 V in reverse across the blue. This is how the bi-directional LED is intended to be used and it will be fine.
As far as I remember, bi-directional LEDs are available with the same colour in both directions. These are suitable for AC indicators and eliminate the requirement for an external diode.
answered 8 hours ago
Transistor
80.2k778173
Because the two LEDs are back to back the maximum reverse voltage applied to one will be the forward voltage, Vf, of the other.
... blue one has 3 V, red one has 1.8 V ...
When the blue LED is lit there will be 3 V in reverse across the red and when the red is lit there will be 1.8 V in reverse across the blue. This is how the bi-directional LED is intended to be used and it will be fine.
As far as I remember, bi-directional LEDs are available with the same colour in both directions. These are suitable for AC indicators and eliminate the requirement for an external diode.
answered 8 hours ago
Transistor
80.2k778173
answered 8 hours ago
Transistor
80.2k778173
answered 8 hours ago
Transistor
80.2k778173
answered 8 hours ago
Transistor
80.2k778173
80.2k778173
add a comment |
add a comment |
Chanho Jeon is a new contributor. Be nice, and check out our Code of Conduct.
Chanho Jeon is a new contributor. Be nice, and check out our Code of Conduct.
Chanho Jeon is a new contributor. Be nice, and check out our Code of Conduct.
Chanho Jeon is a new contributor. Be nice, and check out our Code of Conduct.
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2
As long as the currents are not excessive, the two LEDs should protect each other from excessive reverse voltage.
– jonk
9 hours ago
Just don't decide to take one out momentarily... ie, this is better soldered up than on a breadboard.
– Chris Stratton
2 hours ago