Limiting resistor circuit and limiting resistor component

Abstract

The present invention provides a limiting resistor circuit and a limiting resistor element that suppress thermal runaway of a resistor element that limits inrush current. [Solution] The limiting resistor circuit 1 for limiting inrush current comprises a ceramic resistor element 10 that functions as a first resistor element having a negative temperature coefficient of resistance, and a wire-wound resistor element 20 that functions as a second resistor element having a positive temperature coefficient of resistance and melting due to overcurrent. The ceramic resistor element 10 and the wire-wound resistor element 20 are connected in series with each other. The resistance value of the wire-wound resistor element 20 is smaller than the resistance value of the ceramic resistor element 10, and the absolute value of the temperature coefficient of resistance of the wire-wound resistor element 20 is greater than or equal to the absolute value of the temperature coefficient of resistance of the ceramic resistor element 10.

Claims

1. A limiting resistor circuit that limits inrush current, A first resistive element having a negative temperature coefficient of resistance, It comprises a second resistive element having a positive temperature coefficient of resistance and melting due to overcurrent, The first resistive element and the second resistive element are connected in series with each other. The resistance value of the second resistive element is smaller than the resistance value of the first resistive element. The absolute value of the temperature coefficient of resistance of the second resistive element is greater than or equal to the absolute value of the temperature coefficient of resistance of the first resistive element. The second resistive element is a wire-wound resistive element. Limiting resistor circuit.

2. A limiting resistor circuit according to claim 1, The resistance value of the second resistive element is 5% or more of the resistance value of the first resistive element. Limiting resistor circuit.

3. A limiting resistor circuit according to claim 1, The resistance value of the second resistive element is determined such that the temperature of the first resistive element is lower than the melting temperature of the second resistive element when the second resistive element melts. Limiting resistor circuit.

4. A limiting resistor circuit according to claim 1 or claim 2, The first resistive element is a ceramic resistive element. Limiting resistor circuit.

5. A limiting resistor circuit according to claim 1 or claim 2, The sum of the resistance values ​​of the first resistive element and the second resistive element is 1 ohm or more. Limiting resistor circuit.

6. A limiting resistor circuit according to claim 5, At least the second resistive element is covered with an insulating case or protective film. Limiting resistor circuit.

7. A limiting resistor element that limits inrush current, A first resistive element having a negative temperature coefficient of resistance, It comprises a second resistive element having a positive temperature coefficient of resistance and melting due to overcurrent, The first resistive element and the second resistive element are connected in series with each other. The resistance value of the second resistive element is smaller than the resistance value of the first resistive element. The absolute value of the temperature coefficient of resistance of the second resistive element is greater than or equal to the absolute value of the temperature coefficient of resistance of the first resistive element. The aforementioned second resistive element is a wire-wound resistive element. Limiting resistor element.

8. A limiting resistor element according to claim 7, At least the second resistive element is covered with an insulating case or protective film. Limiting resistor element.

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