Well I started with the 3 watt ndb7875 from DTR and the cheap generic Chinese LED driver. It worked good. I got about 700 from my diode before it barfed. I think I need to possibly beef up my cooling on my diode. Just using the standard Chinese heat sink with a 40mm high speed fan.
So I replaced my 3 watt with a 1.8 watt and a 6 watt. 6 watt for engravings and 1.8 watt for grey scale images. I have not had time to test the 1.8 watt because I am so busy with mirror engravings for Christmas gifts. But I can say the 6 watt is a noticeable upgrade. But anyways on to the driver.
Ebay seller X-Wossee sells a 5 amp laser driver with many great features at a great price. About $50 CAD after shipping from Russia. Came in about 2 weeks. His instructions were easy to understand and implement.
I did not really need a heat sink on my Chinese driver but this 5A driver a large heat sink is a must. First I tried a small copper heat sink about the size of a North Bridge heat sink. That little sucker got so hot it burned my finger when I touched it to see if it was warm… It was warm alright. So I said ok fine. I grabbed a heat sink from an old AMD dual core processor with a 60mm fan, glued the mosfet to the backside, mounted it to my MPCNC and cranked her up. I am running at about 80% of power (4A) and the heat sink is totally cool. The mosfet itself if noticeably warm but not finger cooking good.
The driver has 2 pins for quickly checking a momentary current draw. Thermistor port, and a locking port. All in a tiny package about 1.5" square.
So far this driver is getting 5 stars from me.
Next up for me will be a tec controller to cool my diodes.