Maybe this voltage divider calculator will be helpful. But be aware, it's not that precise, and it's only for relatively low-current loads. If you draw too much current (say, more than 5mA) then you will no longer get 1V out.
If you want a steady, regulated 1V then you'll need a voltage regulator.
If all you want to do is light an LED or something, give us a few more details and we'll try to help you out.
Oh! In that case you'll need a single resistor, between 820 ohms and 1000 ohms, with a 1 watt rating.
Any reason why you're using two 9V batteries for a single LED? It's very much overkill. You're cooking off a great deal of power through the resistor so the batteries won't really last very long.
As steveastrouk said, more information is needed. Maybe you could describe in as much detail as possible the project you are working on and what you are trying to do. That will at least let us know what further questions to ask you.
Comments
Best Answer 11 years ago
What are you trying to achieve ? A resistor may not be the best way, and besides, you need to know the current it will pass.
Steve
11 years ago
Maybe this voltage divider calculator will be helpful. But be aware, it's not that precise, and it's only for relatively low-current loads. If you draw too much current (say, more than 5mA) then you will no longer get 1V out.
If you want a steady, regulated 1V then you'll need a voltage regulator.
If all you want to do is light an LED or something, give us a few more details and we'll try to help you out.
Answer 11 years ago
i want to take 18 volts from 2 nine volts then put it through an led
Answer 11 years ago
Oh! In that case you'll need a single resistor, between 820 ohms and 1000 ohms, with a 1 watt rating.
Any reason why you're using two 9V batteries for a single LED? It's very much overkill. You're cooking off a great deal of power through the resistor so the batteries won't really last very long.
Answer 11 years ago
after the led im gona have a 30 volt cap and a speker
Answer 11 years ago
OK.... So what is it you're trying to build?
Answer 11 years ago
amplifier
Answer 11 years ago
Okay, so what are you using for your amplifier, a transistor, an LM386, or something else?
Answer 11 years ago
transistor, not sure what kind it is
Answer 11 years ago
Do you have a schematic you're working from? I need more information!
11 years ago
As steveastrouk said, more information is needed. Maybe you could describe in as much detail as possible the project you are working on and what you are trying to do. That will at least let us know what further questions to ask you.