A look inside a B10 USB meter (with schematic)

This seems to be a very common USB tester these days. It has USB-C connectors on each side and can measure voltage and current in either direction, with a stated range of 4.5 to 50V and 12A. There is a small, but very readable display. I did some voltage and current tests and it seemed accurate. I thought the display was OLED, but it may actually be LCD. It has a neat feature where it can be switched from a colour display to black and white. Possibly for better clarity - especially for those with different colour perception. Most of the magic is done in software on an ARM Cortex microcontroller, but the current sensing is interesting because it can sense current flow in either direction. Both the op-amp and buck converter chips were hard to find data for. I did an image search for their codes and found a picture from a Russian technical forum, where the post was also trying to identify the chips. This scenario happens a lot, since Russia has a lot of technical geeks. The controls are refreshingly simple. With the buttons on the right of the display, the bottom button rotates the display with each click, or toggles between colour and monochrome with a long press. The top button cycles through the full display, chunky minimal display, current zeroing mode (long press to zero with no load connected), Display intensity and an option to temporarily turn the display off. The meter logs the mAh that has been provided to a load. If not cleared between uses it will continue counting up. To reset it to zero, press and hold the top button. If you want one of these, then here's a typical listing on AliExpress (not a sponsor). It's an affiliate link, but that shouldn't affect the price. https://s.click.aliexpress.com/e/_c3hHoi1R The price can vary, so shop about. The meter may also pop up in the bundle deal area if you add one to your main basket. If you enjoy my videos, you can buy me coffee, cookies and gadgets by supporting the channel on Patreon. You also get early access to videos without adverts, bonus footage and regular quiet Patreon live streams. https://www.patreon.com/bigclive Alternatively, for a single coffee contribution you can use PayPal:- https://www.paypal.com/paypalme/bigclive #ElectronicsCreators