DC brushless fan motor driving circuit
US7386224B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Aug 23, 2005 |
| Grant date | Jun 10, 2008 |
| Priority date | — |
| Expiry date | Dec 4, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P2209/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A DC brushless fan motor driving circuit has a Hall PWM signal generator, a speed signal generator, a PWM driver and a full-bridge switching circuit. The Hall PWM signal generator obtains a Hall sine wave signal from an external Hall sensor and converts the Hall sine wave signal to a varied Hall PWM signal. The speed signal generator is connected to an external PWM input signal to set speed of a fan motor and a low speed voltage to determine a present speed setting signal. The speed signal generator further obtains the varied Hall PWM signal to compare the present speed setting signal to generate a SPWM signal to the PWM driver. The PWM driver outputs a SPWM signal to the full-bridge switching circuit and then coil current is formed close to a sine wave signal to decrease the electromagnetic noise.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.