초록 ▼

A fan control system includes a temperature detecting circuit and a rotation rate control circuit. The detecting circuit includes a first amplifier, a second amplifier, and a thermistor. The rotation rate control circuit includes a first terminal, a second terminal, and a third terminal. The detecti

A fan control system includes a temperature detecting circuit and a rotation rate control circuit. The detecting circuit includes a first amplifier, a second amplifier, and a thermistor. The rotation rate control circuit includes a first terminal, a second terminal, and a third terminal. The detecting circuit detects temperature and outputs a voltage signal. The rotation rate control circuit receives the voltage signal and controls the rotation rate of the fan according to the voltage signal.

대표청구항 ▼

1. A fan control system, comprising: a temperature detecting circuit comprising a first amplifier, a second amplifier, and a thermistor, wherein power terminals of the first amplifier and the second amplifier are to be connected to a first power supply, ground terminals of the first amplifier and th

1. A fan control system, comprising: a temperature detecting circuit comprising a first amplifier, a second amplifier, and a thermistor, wherein power terminals of the first amplifier and the second amplifier are to be connected to a first power supply, ground terminals of the first amplifier and the second amplifier are to be grounded, a non-inverting input of the first amplifier is to be connected to a second power supply through the thermistor, an inverting input of the first amplifier is to be grounded through a first resistor, an output of the first amplifier is connected to the non-inverting input of the first amplifier through a second resistor, the output of the first amplifier is also connected to a non-inverting input of the second amplifier through a third resistor, an inverting input of the second amplifier is to be grounded, an output of the second amplifier is connected to the non-inverting input of the second amplifier through a fourth resistor, the output of the second amplifier outputs a voltage signal; anda rotation rate control circuit comprising a first terminal connected to the first power supply, a second terminal connected to the output of the second amplifier to receive the voltage signal, and a third terminal connected to the fan, to control the rotation rate of the fan according to the voltage signal. 2. The fan control system of claim 1, wherein the rotation rate control circuit comprises a third amplifier, and a metal oxide semiconductor field effect transistor (MOSFET), a drain of the MOSFET functions as the first terminal of the rotation rate control circuit, a source of the MOSFET functions as the third terminal of the rotation rate control circuit, the source of the MOSFET is to be grounded through a fifth resistor and a sixth resistor in series, a non-inverting input of the third amplifier functions as the second terminal of the rotation rate control circuit, an inverting input of the third amplifier is connected to a node between the fifth resistor and the sixth resistor, an output of the third amplifier is connected to a gate of the MOSFET, a power terminal of the third amplifier is to be connected to the first power supply, a ground terminal of the third amplifier is to be grounded.