EEVblog #72 - Let's Design a Product
Why Electrical Engineering Stack Exchange recommends it
Electronics Stack Exchange answerers point people to it for Dave's comparison of three ways to generate a negative voltage rail for an op-amp, and as a build-it-yourself reference for a micro-current measurement device.
Recommended by 3 people across 3 different months, 2011 to 2021.
What it is
A 51-minute episode of EEVblog in which Dave Jones walks through designing a complete product from scratch, using the uCurrent precision current-measurement adapter as the worked example. It covers design decisions along the way, including how to generate a negative voltage reference for an op-amp stage, and links to a full written article.
What people said
Recommends abdullah kahraman · 2011-12 · Electrical Engineering Stack Exchange · on “How to supply a negative voltage from a simple battery or psu?”
First, you should have a voltage suitable with your batteries set up, as Russell said, then, there are several ways to obtain negative voltage referance for your OP-AMP. In one episode of EEVblog, Dave tells 3 options and compares them for a spesific application. Here is the episode where Dave designs a negative voltage referance generator for uCurrent project EEVblog #72 - Let's Design a Product [this video] @ 21:27
Recommends erkan · 2014-06 · Electrical Engineering Stack Exchange · on “op amp level shifter no input situation”
i will check if i can find cheap voltage inverter in my country. I may try No:3 of Dave's solutions: [this video]
Recommends Christianidis Vasileios · 2021-03 · Electrical Engineering Stack Exchange · on “How to find current drain out of a connected USB device?”
You can buy one of these: [LINK] Image found here [LINK] But bare in mind they are not always accurate (if you buy them from aliexpress [LINK] like i did, you will end up with a +- 20mA current error. Another device you can buy (for sure results) is a micro-current measurement device [LINK] [LINK] which you can also build by yourself [this video] . And you can also (if you have an accurate Amp-meter) cut your usb Vcc wire and hook the amp-meter in series, you will see how much mAmps it draws.