摘要 |
A trimming circuit for a semiconductor device performs both simulated fuse breakage and actual fuse breakage by selectively short-circuiting an adjusted device. The trimming circuit includes a switch connected in parallel with the adjusted device. Activating the switch causes the adjusted device to be by-passed or short-circuited. A first external terminal is connected to the switch to apply a first control signal to the switch. A second external terminal is provided for receiving a second control signal. A fuse circuit is connected between a high potential power supply and a low potential power supply and between the first and second external terminals. For hypothetical fuse breakage, the first control signal is activated to activate the switch and by-pass the adjusted device. For actual fuse breakage, the second control signal is activated such that it has a potential greater than the first control signal so that a current flows through the fuse circuit, thereby breaking the fuse. When the fuse is broken, the switch is activated, thereby causing the adjusted device to be by-passed.
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