mrp1232
0
- Joined
- Jun 9, 2011
- Messages
- 16
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OK i have been trying to figure this out for at lease 4 hours straight and its driving me nuts ! :banghead: How is it that for a red laser you need a power supply of 7.2 when the diode needs 3, 1.2 for long life between battery changes and the lm317's dropout voltage is 1.2. Thats only 5.4, wheres the rest of it? On ROG8811 it says that its 7.2 b/c of
Voltage needed by red LD 3v
Voltage needed by regulator to make it work 3v
Additional voltage to get long life between battery changes 1.2v.
Add that up and you get 7.2volts (his words)
Where did the 3 volts for the 317 come from, i never heard of 3v being needed for the 317 to work. I have heard of 317 adj being able to put out 1.2v. So that + 1.2 dropout = 2.4v; that would be the min voltage you could set right ? Maybe there is no dropout V. I am just really tired of trying to figure this out and its late on top of that. Could someone just tell me where i went wrong or what i'm missing.
Thank you and sorry if i said anything noobish.
Voltage needed by red LD 3v
Voltage needed by regulator to make it work 3v
Additional voltage to get long life between battery changes 1.2v.
Add that up and you get 7.2volts (his words)
Where did the 3 volts for the 317 come from, i never heard of 3v being needed for the 317 to work. I have heard of 317 adj being able to put out 1.2v. So that + 1.2 dropout = 2.4v; that would be the min voltage you could set right ? Maybe there is no dropout V. I am just really tired of trying to figure this out and its late on top of that. Could someone just tell me where i went wrong or what i'm missing.
Thank you and sorry if i said anything noobish.