I needed a high-current car USB charger 5V at 2.1A for my iPad, smartphone etc. Chinese LM2596 3A step-down converter modules are for sale on eBay and DX for $1.50 to $4.40 (which is cheaper than I can buy the IC for), so I picked some up. I bench tested them and here are the results and thermal-camera pics at 5V 2.4A output and 13.5VDC input (~81% efficiency). The LM2596 runs 105°C and the diode 112°C ! x-(
As you can see, they run way hot and the diode is only a 1A part. I thought, why run a $450 tablet off a crappy $2 converter, that has no overvoltage protection, no fuse, overheats... I'm building something better...
As you can see, they run way hot and the diode is only a 1A part. I thought, why run a $450 tablet off a crappy $2 converter, that has no overvoltage protection, no fuse, overheats... I'm building something better...