what kind of diode do I need to lower voltage???
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A Zener diode with a small resistor will regulate voltage. Just find one with the value you want.
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Zener Diode or more specifically, a TVS Diode. .68-.72ohms with an output of roughly 4.8-5.5v is roughly what you want.
A zener diode is used to provide a reference voltage. It cannot be used by iself as a voltage reducing power supply!
Using a zener dode
A zener diode provides a good way to achieve a stable lowered voltage but requires a power tansistor or mosfet to handle the load current. The zener diode is used in reverse; it has a specific voltage drop used this way (forwards it works like a normal diode).
Basically the zener sets the base voltage of the transistor and there will be a further drop of about 0.6V through the transistor, so to get say 4.5V out the zener required qould be 4.5+0.6 = 5.1V (some transistors have a lower forward drop than 0.6v);
Example circuit using a power zener diode with a power transistor:
http://sound.westhost.com/appnotes/an007.htm
See also:
http://nptel.iitm.ac.in/courses/Web...uits/lecturers/lecture_27/lecture27_page3.htm
Using power diodes (easy solution)
Modern power diodes have a 0.35V forward drop (some versions might be 0.7v). Such as the 1N4001. Just connect these in series to drop the voltage the required amount (3 of them to drop by just over 1V). These diodes are robust - no danger from connecting the wrong way, simply no current flow.
Using a voltage regulator (fairly easy solution)
Input voltage needs to be about 1.5V higher than the output (check specifications). Contains a zener and power transistor in one easy-to-use 3 pin package (and perhaps output sensing and comparator for extra stability).
Example:
http://www.electro-tech-online.com/...h-current-power-supply-circuit.html#post80417
(see also the notes below that post)
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Really? Interesting .....
Yeah, and as you stated, finding a diode that can carry more than 50mA - 100mA can be quite the challenge!
THAT'S the code I was trying to remember!!! IN4001....I just did a quick search and also found the IN4004, which on the Source's website says somewhere has a voltage drop of .8V which is around what I was aiming for.
Thanks guys, hope this works.
Thanks guys, hope this works.
Go to texas instruments website and search for "UCC383TDKTTT-5" It is a low drop out (LDO) voltage regulator. Max Vin is 9v, Min Vin is 5.45V. Output is fixed at 5V. You want the DDPAK/TO-263 form factor.
I have been using this chip for a month or so with no issues.
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Nuck used this diode (1N4001) - he posted on this thread
http://www.e-cigarette-forum.com/fo...93-nuked-hell-out-my-atmoizer.html#post282078
edit: took too long to post!- I see Kinabaloo posted the same diode
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youfill ...
do you have a meter? i ask, because if you are using 2 RCR123's in succession rated at 3.0v each, chances are you are probably closer to 7v than 6v. You may want to get a couple of them and test them!
Just my $.02 cents
do you have a meter? i ask, because if you are using 2 RCR123's in succession rated at 3.0v each, chances are you are probably closer to 7v than 6v. You may want to get a couple of them and test them!
Just my $.02 cents
TI will send a free 5-pack of the voltage regulators that Laredo referenced above....for those who wish to try them out.
Nice thing about them is they always set the output at 5V.
Nice thing about them is they always set the output at 5V.
yes they will! Laredo ... Do you happen to have a pic of the chip? I'm looking at the specs PDF but can't visualize!
Check out page 18 of 22 on the PDF. That is the form factor I used.
Gotcha Laredo ...
Also found this on Digikey:
I use a smaller form than that. It looks like this:
A good suggestion
For a small voltage drop and with limited space, the 1N4001 diodes are ideal (small and robust). For a more professional solution the voltage regulator is simple and also robust.
For more examples of electronic circuits of all kinds, see:
http://www.e-cigarette-forum.com/fo...-electronics-resource-modders.html#post286125
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