Patent ID: 9559668
Date: 2017-01-31
CPC Classifications: H03K

Claim:
1. A drive circuit, comprising: a gate drive node; a power source node; an output transistor configured to be connected between the gate drive node and the power source node, and to flow a current into the gate drive node; an input transistor configured to form a current mirror with the output transistor, and to have a smaller size than the output transistor; an operational amplifier configured to output a control voltage depending on a potential difference between a voltage received as input depending on a voltage of the gate drive node, and a constant voltage lower than a voltage of the power source node; a control transistor configured to include a control electrode receiving as input an output of the operational amplifier, and to be connected in series with the input transistor; and a constant current source configured to be connected in series with the control transistor, the constant current source including: