When everything is good, turn PCB around, check alignment, solder another corner pin, and check alignment again – if misaligned, heat up the joint and re-align. If after making this joint pins become misaligned, heat the solder joint, melt the solder and re-align the part. Photo 3b shows pins aligned to pads and a corner pin soldered.

Photo 3a shows correct placement – a notch on the case is facing power supply side of PCB. Boom-mounted lighted magnifier is nice to have but optional. Solder wick is helpful when too much solder was applied accidentally. Flux pen or a bottle of liquid flux (which is really rosin diluted in alcohol) and a brush is also necessary – the secret of successful SMT soldering is generous flux application. I’m using ordinary temperature-controlled soldering iron, similar to one used in the video above. Nevertheless, be extra careful with multi-pin parts placement – once 3 pins of a part are soldered to PCB, fixing mis-alignment becomes very difficult. Don’t be scared – the parts you will be dealing with are quite a bit bigger. If you are unfamiliar with SMT soldering, watch this excellent SMT Soldering 101 video by Curious Inventor. Parts are big enough to be placed without aid of a a microscope and soldered by hand. The kit has been designed for easy assembly. To distinguish between them, see description for number 11. D-size package, usually tan but may be black, like number 11. On the picture, 686 means 68uF, 10 means 10V. Marked with 2 numbers, first indicating capacitance, second – rated voltage. Also, capacitance value of input cap is around 20uF, whereas output cap has 68-100uF. Input capacitor is usually rated to 35V, output – only to 10V.

To distinguish between them, read second number, which indicates voltage. D-size package, usually black but may be tan, like number 12. 6-10uH inductor, Sumida CDRH5D18 or similar. Linear Technology LT1376-5 buck controller IC. Very hard to distinguish from number 5, the only way to avoid mix-up is to keep them separated. Most of them have distinctive shape and therefore easily identifiable, but beware of number 6! The rest of the parts are present only in “Full” kit. Very hard to distinguish from number 6 in “Full” set, the only way to avoid mix-up is to keep them separated. Four on a tape in “Isolator Only” set, five in “Full” set. Usually black in color, but may also be blue. Four on a tape, marked “240”, “24R0”, or similar. Three on a tape, marked “105” (or “501” if you are holding it upside down) on top. This is the largest of small parts, you won’t miss it. Usually comes on a tape, but may be packaged differently, for example, in a piece of IC “tube”. Wide 16-pin SOIC package, clearly marked on the top. Analog Devices ADuM4160 IC, the heart of the circuit. They will be soldered very late in the build, together with connectors – for now it’s best to put them away. Used to program USB speed on both sides of the isolators. A pair of 0.1″ headers with 2 pin jumpers. Again, “Isolator Only” set is on the left aligned in a single column. For next several steps, a pair of tweezers and magnifier glass will be helpful. The easiest way to get parts out of the bag is to cut the bag along the long edge with scissors. Some parts are mounted on a tape – it is generally good idea to keep them this way until the moment you are ready to solder them. These parts are also lightweight so sneezing into a pile of parts is not recommended. No matter which kit you are building, dealing with small unmarked parts is inevitable. “Full Kit” on the right contains more parts, as well as one extra connector. Parts are in the lower compartment, PCB – in the middle of the bag, and connectors are on the top. When parts kit arrives in the mail, it usually looks like one on Photo 1 (click on it to make it bigger). In this manual, I give step-by-step instruction on building USB isolator kit and also talk about tweaking and modifying the circuit for certain applications.īoth “Isolator Only” and “Full” Kits are covered.īefore starting assembly, please download the schematic. It is reliable and quite affordable way to provide galvanic isolation between host PC and USB peripheral. USB Isolator kits, released in October 2009, has been popular among PC-based test instrument users, software-defined radio operators, and DIY audio builders, to name a few. This is assembly guide for Analog Devices ADuM4160-based full/low speed USB Isolator kits from Circuits At Home.

Diyaudio usb isolator