Input and output voltage?

Ok, This is where i am getting really confused.
I just need help with what factors i need to know about when buying the materials needed to buy a laser, like a driver or what type of batteries.
For Example,
-Input voltage
-Output voltage
I cant seem to find anything where it could tell me what i need to be looking for when buying a driver and using batteries.

Here are some brief questions,
Will the phr-803t Run off of this driver?
If so, what batteries do i need to use?

Yes, a PHR will run off that driver.

When considering drivers for laser diodes, the voltage isn't critical, BUT, you need to make sure your driver is capable of the laser diodes forward voltage.

In general, for red diodes it's about 3V, green lasers (DPSS, not diode) are about 2V, and for 405nm and 445nm diodes, it's around 4.5-5V. The new direct green diodes have a pretty high Vf of around 8-9V, so not many drivers will work with them yet.

There are generally 3 types of drivers:
Linear - The input voltage needs to be higher than the diode Vf, this driver is pretty inefficient, but it's the simplest and pretty common.
Buck - These drivers also need an input voltage higher than the diodes Vf, but they're more efficient than linear drivers, thus don't generate as much heat.
Boost - These drivers can have input voltages lower than the diodes Vf, as the name suggests, they can boost the voltage higher.

Sometimes you can get a combination of buck/boost, which allows your input voltage to be higher or lower than the diodes Vf, but it's not too common in this hobby.

For example, to run a 445nm diode from a single lithium battery, you'd want a boost driver, but if you wanted to run a DPSS green (and probably even a red) from a single lithium battery, a linear or buck driver would be fine.

The only other parameter you need to consider is output current. The safe limit for a PHR is around 90mA, so pretty much any driver will handle that, just consider what I said above about the driver types.

Thank you so much! This could not have been any more clearer.

Forgot to mention that a 405 and 445nm diode usually can run off a single lithium battery, however you'd definitely want a buck driver, and the diode may not function for the batteries full capacity. Better to use a boost, but you could probably get away with buck if battery lifetime wasn't a huge concern. The flexdrive is a good choice for a PHR if you can obtain one, as it'll make use of all the batteries capacity.

Things said:

Forgot to mention that a 405 and 445nm diode usually can run off a single lithium battery, however you'd definitely want a buck driver, and the diode may not function for the batteries full capacity. Better to use a boost, but you could probably get away with buck if battery lifetime wasn't a huge concern. The flexdrive is a good choice for a PHR if you can obtain one, as it'll make use of all the batteries capacity.

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So here is another question. It says on the manual of the flex drive that the input voltage is 2.0 - 5.5V, and to operate a 405nm you need 4.5v. so from what i have read, you add them together. Then that gives you the amount of voltage you need. Is that correct?

Hello Zetta,

No, that is not correct. Your diode gets its input voltage from the driver, which in turn, gets its voltage from your battery. If the input V of your driver is 2.0-5.5, then your 3.7V batter will give 4.2 on a full charge, so you're right in the middle of what you need for the driver. BTW, good luck finding a flex-drive!
The driver will take what it gets from the battery and deliver the V to the diode. You needn't worry about the diode Vf except if you're setting a driver's current output, and in selecting your driver/battery combination.

ZettaByteLP said:

So here is another question. It says on the manual of the flex drive that the input voltage is 2.0 - 5.5V, and to operate a 405nm you need 4.5v. so from what i have read, you add them together. Then that gives you the amount of voltage you need. Is that correct?

Click to expand...

The flexdrive is a boost driver, it is designed for single battery builds. It will boost the battery voltage up high enough to run the PHR, you only have to worry about current.

Things said:

The flexdrive is a boost driver, it is designed for single battery builds. It will boost the battery voltage up high enough to run the PHR, you only have to worry about current.

Click to expand...

oh, ok i didnt know that. but how will i know how much it boost's the voltage?

Things said:

In general, for red diodes it's about 3V, green lasers (DPSS, not diode) are about 2V, and for 405nm and 445nm diodes, it's around 4.5-5V. The new direct green diodes have a pretty high Vf of around 8-9V, so not many drivers will work with them yet.

Click to expand...

Hi, Regarding the output V of a 532nm driver. Can I use this to power a 808nm diode which requires about 2.2v@1.2A? I'm looking to power a 1,5W diode but I want a small driver to fit in a handheld laser. (I'm a noob in the laser world.):yh:

Thanks.

miku said:

Hi, Regarding the output V of a 532nm driver. Can I use this to power a 808nm diode which requires about 2.2v@1.2A? I'm looking to power a 1,5W diode but I want a small driver to fit in a handheld laser. (I'm a noob in the laser world.):yh:

Thanks.

Click to expand...

Yes. 532nm driver drives 808nm diode. As for current requirements, iono.