Brush less motor control

The maintenance on a small electric fan this time gave me an indispensable opportunity to study further about Brush less motor control. Though I thought this electric fan must have been fabricated a half a century ago judging from the outside of view, my perception was out of point. Consideration about recent brush less motor control technology, this one is produced few years ago.
Opening the base part proved that the fan was produced recently without doubt, because I found out brush less motor controlling module filled with sophisticated semi-conductor wiring design.
The main controller is consists with a programmed microcomputer and inverter circuitry, the former produces Pulse Width Modulation output and the latter amplifies the signals with the drivers to activate the brush less motor. Many Field Effect Transistors, Insulated Bipolar Transistors and Intelligent Power Devices are included in a small piece of the Semi-Conductor device. Pulse Width Modulation technology is invited here inside of a vintage look electric fan.
It is often the case to be surprised by the recent remarkable advance in electric technology.