I need help determinig correct voltage.

[Martin Rodriguez]

I have a device that I took off an Avermedia document camera, It has 4 lasers and bright white LED's I would like to power it with batteries, but how can I find out how much voltage is need it?

 

[kellys_eye]

Show a picture of it.

The voltage is 'fixed' according to the type of device but its current requirement is quite specific and can't be guessed at (safely).

What do you want to power? The LED or the lasers? Sure they're lasers?

 

[Martin Rodriguez]

See I'm powering it with a 9v battery, but I don't know if I'm giving it the correct voltage I really don't want to fry the LED's.

 

[kellys_eye]

Seems as if the LEDs have some form of current limiting and/or control on the lower circuit board. Do you have any idea what the original supply voltage to the equipment was?

I suspect there will be a voltage regulator in there somewhere as the LEDs 'look' to be lit appropriately - just connecting a battery across them could damage them. The 'lasers' (if that's what they are) would require additional control - again seemingly part of the lower circuit board???

Potentially some control components on the reverse of the top board too???

 

[AnalogKid]

What was the battery voltage for the camera?

ak

 

[Cannonball]

I see that you were running it with a 9 volt battery. Open the circuit at the positive terminal of the battery and
insert an amp meter to read the current. Compare this with the specs of the LEDs and lasers. If this is to much
current, take the difference of what you read from what the specs are. Divide this into 9. Install a resistor of this
value into the circuit. That is what I would do if it were me.