Gate driver circuit and motor driving device

Abstract

To provide a gate driver circuit capable of detecting an under voltage state of a bootstrap voltage.SOLUTION: An under voltage detection circuit 260 compares a potential difference between a bootstrap line 202 and an output line 204 with a threshold voltage Vth. A voltage line 205 generates a voltage lower by a predetermined voltage dV than the bootstrap line 202. A current mirror circuit CM1 is connected to the bootstrap line 202. A first resistor R1 and MOS diodes Md1, Md2 are connected in series between an input node of the current mirror circuit CM1 and the output line 204. A second resistor R2 is connected between an output node of the current mirror circuit CM1 and the voltage line 205. A comparator 262 compares a voltage drop VR2 across the second resistor R2 with a threshold voltage Vth.SELECTED DRAWING: Figure 2

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