Cooling Fan Velocity Control Apparatus Using Timer and Temperature Sensor

Abstract

An apparatus and method for controlling a velocity of a cooling fan using a timer and a temperature sensor in a set-top box (STB) are provided. An apparatus for controlling a velocity of a cooling fan in an STB may include a temperature sensor unit to change a resistor to be in inverse proportion to an internal temperature, using a thermistor, a timer unit to generate a pulse signal using a capacitor and the resistor of the temperature sensor unit, a switching unit to turn on/off applied voltage, using the generated pulse signal, and a power source unit to apply the voltage to the switching unit.

Description

CROSS-REFERENCE TO RELATED APPLICATION[0001]This application claims the benefit of Korean Patent Application No. 10-2012-0106836, filed on Sep. 26, 2012, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference.BACKGROUND[0002]1. Field of the Invention[0003]The present invention relates to an apparatus and method for controlling a velocity of a cooling fan using a timer and a temperature sensor in a set-top box (STB).[0004]2. Description of the Related Art[0005]In most cases, set-top boxes (STBs) are basically operated at all times. Heat may be frequently generated in STBs, which may cause fire hazards. Accordingly, to cool heat generated within an STB during an operation of the STB, a fan, namely a cooling fan, may be attached, and a rotative velocity of the cooling fan may be controlled to prevent performance from being reduced due to heat generation and to maximize the performance.[0006]However, in current STBs, a method of actively ...

AI Technical Summary

Benefits of technology

[0017]According to embodiments of the present invention, there may be provided an apparatus that may actively control a velocity of a cooling fan based on a degree of heat generation, by using an NE555 timer, and a negative resistance of a temperature sensor, namely a thermistor, when the cooling fan needs to be used due to heat generated in a central processing unit (CPU) that does not have a function of a temperature sensor.

[0018]Additionally, according to embodiments of the present invention, it is possible to improve a function of reducing noise of a cooling fan by actively controlling a velocity of the cooling fan based on a temperature, when the cooling fan is used to reduce heat generated in a product in a CPU that does not have a function of a temperature sensor. In addition, it is possible to reduce costs, since a separate external microcontroller is not required.

Problems solved by technology

In most cases, set-top boxes (STBs) are basically operated at all times. Heat may be frequently generated in STBs, which may cause fire hazards.

However, in current STBs, a method of actively controlling a velocity of a cooling fan based on an increase in a temperature is not provided.

The above method has a limitation on controlling of a velocity of a cooling fan in response to an increase in an internal temperature of a product.

Additionally, when a cooling fan is set to rotate at a high velocity using a currently provided fan velocity control method, a level of generated noise may increase, as a rotative velocity increases.

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