Wire Gauge

roeb

I am going to be pulsing a laser diode at around 2 Watt (room temperature) with a frequency of around 1-10 MHz. Right now I'm planning on using 26 AWG wire. Anyone have any thoughts on whether this is okay? Is the gauge okay? Since it's pulsed I assume I don't have to worry as much about heat dissipation..

I'm not sure of the actual current draw but it should be around 1 - 2 amps.
According to this website http://wiki.xtronics.com/index.php/Wire-Gauge_Ampacity
the max free-air amperage is 2.2 A. I'm kind of skirting the boundary there...

Thanks,
roeb

berkeman

Why are you using 26AWG? How long is this cable? Since you should use twisted pair (TP) cable, why not use a piece of CAT-5 or CAT-6 TP? That's 24AWG, and easy to come by...

roeb

Hey, I guess I'm not using that stuff because I'm kind of short on supplies.

So the length of wire itself is less than 10 cm. I'm just soldering a BNC connector to a veroboard and using the AWG 26 wire to connect to diode. The signal pin of the BNC connector itself doesn't look all that much larger than the wire I'm using, but I'm not quite sure if I need to worry about the power that's going through the wire.

berkeman

I don't think the AWG is a problem. But depending on the application, you may need to be careful about transmission line considerations. Do you have a 50 Ohm coax cable coming from somewhere that connects to the BNC connector on your board? Are you using TP to connect the center conductor and ground ring of the BNC to your diode's connections? Or are you using a ground plane on your board to route the ground of the BNC to the - terminal of the laser diode?