| 摘要 |
PURPOSE: A trimming circuit is provided to monitor the state of an anti-capacitor without using a high voltage comparator by measuring a base current of a transistor. CONSTITUTION: A trimming circuit is composed of a transistor(T5) detecting a cutting of a capacitor and a current mirror, generating a reference current, is composed of transistors(T6,T7) connected to GND and transistors(T5,T8) which protect excessive voltage from being supplied to a base of transistor. If the capacitor is cut and the node(11) is connected to GND very little current is provided to the base of transistor, so the transistor becomes turn-off or the capacitor is not cut and the node is not connected to GND, and so the transistor becomes turn-on.
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