Timeline for Why is the LM7812 getting hot in this circuit?
Current License: CC BY-SA 4.0
16 events
| when toggle format | what | by | license | comment | |
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| Aug 17, 2023 at 3:51 | vote | accept | Hazardous Voltage | ||
| Jun 22, 2023 at 17:58 | comment | added | Hazardous Voltage | no it won't drive a big load circuitry it would be just an optocoupler so quite low power | |
| Jun 22, 2023 at 4:48 | comment | added | periblepsis | @HazardousV The opamp will be itself driving some circuitry. I'm wondering about everything that follows. | |
| Jun 22, 2023 at 2:51 | comment | added | Hazardous Voltage | @periblepsis I had stated what is the use of it in the question above, it would drive an op amp(lm358) | |
| Jun 22, 2023 at 0:57 | answer | added | user338146 | timeline score: 2 | |
| Jun 22, 2023 at 0:21 | comment | added | periblepsis | @HazardousV I'm getting the idea that you seem stuck on supplying from a 60 V supply -- that you intend on keeping it for whatever reasons but that from it you'd like 12 V, as well. It sounds as though you are only driving an LED from all this? Is all this work just to drive an LED at 20 mA? Or do you have other plans once the LED is working as you expect? (Note: 20 mA at 60 V is 1.2 watts. Only a tiny portion of that will be in the LED. Most of it elsewhere unless you go towards switching supply.) | |
| Jun 21, 2023 at 23:21 | history | edited | Hazardous Voltage | CC BY-SA 4.0 |
added 112 characters in body
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| Jun 21, 2023 at 22:59 | answer | added | TimWescott | timeline score: 4 | |
| Jun 21, 2023 at 22:56 | history | edited | Hazardous Voltage | CC BY-SA 4.0 |
added 58 characters in body
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| Jun 21, 2023 at 22:55 | comment | added | TimWescott | Please edit your question with the information about the input voltage to the regulator. It's a Stackexchange thing -- the questions and answers should be stand-alone, without anyone having to dig through the comments to understand them. So when you have additional information or corrections -- edit the question. | |
| Jun 21, 2023 at 22:53 | answer | added | Justme | timeline score: 1 | |
| Jun 21, 2023 at 22:48 | comment | added | Hazardous Voltage | sorry for the lack of information, the input voltage to the regulator as I measured is 60V, yes it exceeds the datasheet specs for that I limited it with 330ohm resistor. yes the led has a 680ohm resistor connected in series and it draws maximum of 20ma | |
| Jun 21, 2023 at 22:35 | answer | added | user319836 | timeline score: 1 | |
| Jun 21, 2023 at 22:30 | comment | added | Justme | What's the input voltage to regulator, and how much is the LED current? Does the LED have a resistor or is it just connected directly to 12V? Or is it some sort of 12V LED module? Please add in more info about your circuit. | |
| Jun 21, 2023 at 22:16 | history | edited | JYelton | CC BY-SA 4.0 |
Capitalization/spacing; restated question in body
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| Jun 21, 2023 at 22:12 | history | asked | Hazardous Voltage | CC BY-SA 4.0 |