Input protective apparatus of semiconductor device
First Claim
1. An input protective apparatus for a semiconductor device (Q3), comprising an MOS transistor (Q4) having one active layer connected through a first resistor element (R1) to an input node of said device (Q3) and another active layer connected to a ground terminal of said device, a gate of said MOS transistor formed with a thick oxide insulating film,which further comprises an external terminal (11) receiving an input signal to be applied to the input node of said semiconductor device (Q3) and a second resistor element (R2) connected between said external terminal (110 and one of the active layers of said MOS transistor (Q4),a resistance value R1 of said first resistor element (R1) and a resistance value R2 of said second resistor element (R2) having the relation R1 >
- R2, and said MOS type transistor being formed such that an on-resistance R3 thereof satisfies a relation R3 <
<
R2.
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Accused Products
Abstract
An input protective apparatus for a semiconductor device (Q3) comprises an MOS transistor (Q4) having a thick gate insulating film formed therein. The MOS transistor (Q4) has one active layer connected to an input terminal (11) through a second resistor element (R2) and connected to a semiconductor device (Q3) to be protected through a first resistor element (R1), and an other active layer connected to a ground terminal. The input protective apparatus is adapted such that a resistance value R1 of a first resistor element (R1) and a resistance value R2 of the second resistor element (R2) satisfy the relation R1 >R2, and the on-resistance R3 of the MOS transistor (Q4) and the resistance value R2 satisfy the relation R3 <<R2.
9 Citations
19 Claims
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1. An input protective apparatus for a semiconductor device (Q3), comprising an MOS transistor (Q4) having one active layer connected through a first resistor element (R1) to an input node of said device (Q3) and another active layer connected to a ground terminal of said device, a gate of said MOS transistor formed with a thick oxide insulating film,
which further comprises an external terminal (11) receiving an input signal to be applied to the input node of said semiconductor device (Q3) and a second resistor element (R2) connected between said external terminal (110 and one of the active layers of said MOS transistor (Q4), a resistance value R1 of said first resistor element (R1) and a resistance value R2 of said second resistor element (R2) having the relation R1 > - R2, and said MOS type transistor being formed such that an on-resistance R3 thereof satisfies a relation R3 <
<
R2. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 16, 17, 18, 19)
- R2, and said MOS type transistor being formed such that an on-resistance R3 thereof satisfies a relation R3 <
-
15. An input protective apparatus for a semiconductor device (Q3), comprising an MOS transistor (Q4) having one active layer connected through a first resistor element (R1) to an input node of said device (Q3) and another active layer connected to a ground terminal of said device, a gate of said MOS transistor formed with a thick oxide insulating film and connected to said ground terminal,
which further comprises an external terminal (11) receiving an input signal to be applied to the input node of said semiconductor device (Q3) and a second resistor element (R2) connected between said external terminal (11) and one of the active layers of said MOS transistor (Q4), a resistance value R1 of said first resistor element (R1) and a resistance value R2 of said second resistor element (R2) having the relation R1 > - R2, and said MOS type transistor being formed such that an on-resistance R3 thereof satisfies a relation R3 <
<
R2.
- R2, and said MOS type transistor being formed such that an on-resistance R3 thereof satisfies a relation R3 <
Specification