Negative feedback amplifier with electrostatic discharge protection circuit

摘要

A negative feedback amplifier which alleviates reduction in band width and effectively protects an amplifier from electrostatic discharge (ESD). A node is provided at the midpoint of a feedback resistor connected between an output terminal and an input terminal of an amplifier. Each of ESD protective diodes are connected between the node and respective power terminals. ESD threshold voltage and band width vary in accordance with the resistance of a resistor between the input terminal and the node. Setting the resistance of the resistor at 10 to 100Omega makes it possible to secure the necessary ESD threshold voltage while hardly reducing band width.