Archive for October 2016

How does Vacuum Cleaner Clean/Dirty Indicator Work?

I have always wondered how the clean/dirty indicator on my Hoover vacuum cleaner works. So when it was time to replace it with a new one, I opened up the old vacuum and took out the “dirt finder” circuit board. As you will see in the video below, it is actually quite clever! Continue reading ‘How does Vacuum Cleaner Clean/Dirty Indicator Work?’ »

Linear MOSFET and Its Use in Electronic Load – Update

In my previous post, I discussed why it is beneficial to use linear MOSFETs in electronic load and performed a couple of experiments using a single IXYS’ IXTK90N25L2 linear MOSFET. The electronic load was able to dissipate around 150W before the case temperature of the MOSFET reached 90°C. Continue reading ‘Linear MOSFET and Its Use in Electronic Load – Update’ »

Linear MOSFET and Its Use in Electronic Load

Power MOSFETs are widely used in switch mode applications such as pulse width modulated electrical motor controllers and switching mode power supplies. While they are also routinely used in linear mode applications such as power amplifiers and linear power supplies, standard MOSFETs are prone to secondary breakdowns due to hot-spotting or current focusing when operated in linear mode. Continue reading ‘Linear MOSFET and Its Use in Electronic Load’ »

A Dual Sensor Fan Controller Build

A while back, I added a fan controller to my Topward 6603A power supply. Later on, when I bought a used programmable power supply (PPS-2322) I had to do the same thing. Both of those builds were done on protoboards but I had a feeling that many of my other projects could use a similarly designed fan controller as well. So I thought why not just have the PCB professionally made? Continue reading ‘A Dual Sensor Fan Controller Build’ »