Review on CanaKit Raspberry Supply Adapter Listed by Jim Velasco

The attached image shows the measured IV curves for this power supply compared to a 2.0A power supply (Kootek). I generated them using an RPi-based IV curve tracer I made for solar panels (search "IV Swinger" on YouTube and/or GitHub if you want to learn more about it). It's not designed for such low voltages, but it worked quite well. The IV curves show current (I) and voltage (V) for various resistances (R). This tells the story of how the source powers various loads (power = I*V). You can see that both sources have an open circuit voltage of 5.3V. This is the lowest right point. R = ∞Ω, I = 0A, P = 0W. The upper left points of each curve are closest to R=0 (short circuit) that we can measure (R=0.94 ohms due to wiring resistance). You can see that Kootek is outputting about 3A of current and Canakit is outputting about 3.8A. But at this point both voltages are well under 5V (under 3V actually). An interesting point is where the curves cross their current valuations. The Kootek 2.0A power adapter exceeds 2.0A at about 4.6V (2.0*4.6=9.2W). Canakit's 2.5A power supply exceeds 2.5A at about 4.5V (2.5*4.5=11.25W). Both are well below 5V. Probably high enough that the RPi didn't collapse but just cut through it. Another point of interest is the curve transition at 5.0V. Kootek's 2.0A supply voltage crosses 5.0V at about 0.8A (0.8*5.0=4.0W). Canakit's 2.5A power supply exceeds 5.0V at about 1.0A (1.0*5.0=5.0W). People who claim that this power supply doesn't deliver 2.5A are right - if they expect it to deliver 2.5A at 5.0V. Crucially, however, is the PSU sufficient for the RPi 3 that it delivers proportionally more power than the 2.0A PSU that worked great for me with the Gen 1 RPi B+. For this reason I give four stars. For those with specific voltage requirements at rated current (or otherwise) you can read the IV curve values in my appendix.