Fan speed control circuit
US8860351B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 14, 2012 |
| Grant date | Oct 14, 2014 |
| Priority date | — |
| Expiry date | Feb 8, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P7/06
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A fan speed control circuit is provided. The circuit includes a sensor, a control chip, a first integrated circuit, an integrated operational amplifier, a second integrated circuit, and a feedback comparator. The sensor senses a temperature of an electronic component. The control chip outputs a PWM signal corresponding to the temperature to a fan. The first integrated circuit and the second integrated circuit respectively generate a first equivalent voltage and a second equivalent voltage. The integrated operational amplifier amplifies the first equivalent voltage to generate an upper limit voltage and reduces the first equivalent voltage to generate a lower limit voltage. The feedback comparator compares the second equivalent voltage with the upper limit voltage and the lower limit voltage to generate a comparison value. The control chip adjusts the duty cycle of the PWM signal according to the comparison value, and outputs the adjusted PWM signal to the fan.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.