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Can you explain the components continuously operated at the same time?

Latest Updated:09/02/2013

Question:

When the same component is continuously operated at the same conditions, will turn-off delay time increase due to aging deterioration or other reasons? On page 19 of Power MOS FET Absolute Maximum Ratings and Electrical Characteristics (REJ27G0017-0200/Rev.2.00), a method of calculating switching time using gate charge characteristics is shown. If turn-off delay time in this document corresponds to formula 26 on page 20, is it correct to think that turn-off delay time will increase if Cin or Rs increase over time, and decrease if Cin or Rs decrease over time?

Answer:

The relational expression for turn-off delay time td(off) is formula 30 shown on page 21 of technical document REJ27G0017-02. The Rs cited in formula 30 on page 21 is explained simply as the "signal source resistance of the pulse generator". However, for the actual Rs this needs to be replaced with "pulse generator resistance + input resistance + internal gate resistance of the MOSFET". Formula 30 should be thought of as a reference for how values will increase or decrease.

Suitable Products
Power MOSFETs for General Switching