This AN1449 application note describes the software of a low-cost phase-angle motor control drive system based on an OTP version of the ST6200C microcontroller and a BTB16-600CW snubberless triac.
This document describes the software for a low-cost phase-angle motor control drive system based on the ST6200C OTP microcontroller and a BTB16-600CW snubberless triac. The system is designed for applications such as vacuum cleaners, power tools, food processors, and lighting dimmers, utilizing an evaluation board named UMCO1EVAL.
The microcontroller implements speed control via a potentiometer, soft start to reduce inrush current, and mains period measurement to ensure accurate motor control despite RC oscillator variations. The software manages gate pulse generation for the triac, timing definitions for phase angle control, and includes subroutines for power-on reset and soft start logic.
| Microcontroller | ST6200C |
|---|---|
| Triac | BTB16-600CW |
| Evaluation Board | UMCO1EVAL |
| Max Motor Power | 1500 W |
| Gate Current | 60 mA |
| Phase Angle Resolution | 0.7 degrees |
| Clock Accuracy | +/- 20% |
The mains power line period is measured and used as a time base to control the motor accurately, compensating for RC oscillator variations.
This board is able to drive a universal motor up to 1500 W.