For testing USB sockets, power supplies and connected loads!

In this video I use the USB Power Monitor (see link below) to test USB Charger cables and see what losses they can potentially have.

Simple USB Power Meter
http://hackaday.com/2015/09/07/simple-usb-power-meter/

The device measures voltage and current and displays them, along with the calculated power, on the small 0.5″ OLED display. The circuit is built around an ATmega328. To keep the board size small, and reduce component count, the microcontroller is run off its internal 8MHz clock. A low-resistance shunt provides current sensing which is amplified by the LT6106 a high side current sense amplifier before being fed to the 10 bit analog port of the ATmega. A MCP1525 precision voltage reference provides 2.5V to the Analog reference pin of the microcontroller, resulting in a 2.44mV resolution. Voltage measurement is via a resistive divider that has a range of up to 6V.

The OLED display has a SPI interface and requires the u8glib library. The project uses all SMD parts

http://www.electro-labs.com/diy-usb-line-power-meter-stick/

Over the last decade or so, USB has somehow changed. It’s not just for connecting printers, keyboards, mice, and webcams any more. It’s not even just for stuff you would have plugged into a serial port. It’s a power outlet. If you want to charge your phone, plug it into a power outlet that can deliver up to 2.5 Watts.

Being a power outlet, having a device to measure current, voltage, power, and all the other intricacies of the what’s going on inside a USB cable would be neat. The USB Tester from Fried Circuits is that device.

The Fried Circuits USB tester isn’t so much a single device, but a small set of tools that allow you to probe everything going on inside a USB cable.

In its simplest form, it’s just a board with a USB A connector at one end, a USB micro connector at the other, and breakouts for measuring current, voltage, the differential data signals, and that weird ID pin that’s useful if you’re working with USB chargers or OTG devices.

USB Tester 2.0 Bundle
http://store.hackaday.com/products/usb-tester-2-0

It’s a small board with a USB Micro B connector at one end, a ‘normal’ USB A receptacle at the other end, and test points in between. It does one thing, and it does it well. If you’re down with experimenting with USB, the ID pin on the Micro B connector is also broken out. If you’re developing something with USB OTG, this will make things easier.

The logging and graphing capabilities of the backpack are incredible. With the app developed just for the USB Tester 2.0 backpack, you get live feedback of the current, voltage, wattage, and the voltage on the USB data lines. All the data can be saved to a file, allowing you to do fancy power analysis of USB peripherals.

I’m not even using WIFI, just 3G .. Anyhow, superb blog!