Patent ID: 9494964
Filing Date: 2016-11-15
CPC Classification: G05F,H02J,H02M,H03K

Claim Text:
1. A gate drive circuit comprising: a modulation circuit that generates a first modulated signal by modulating a first radio-frequency wave in accordance with a first input signal, and a second modulated signal by modulating the first radio-frequency wave in accordance with a second input signal different from the first input signal; an isolator that includes a plurality of electromagnetic resonance couplers, the plurality of electromagnetic resonance couplers including a first electromagnetic resonance coupler that isolatedly transmits the first modulated signal and a second electromagnetic resonance coupler that isolatedly transmits the second modulated signal; a first rectifier circuit that generates a first signal by rectifying the first modulated signal transmitted from the first electromagnetic resonance coupler; a second rectifier circuit that generates a second signal by rectifying at least a part of the second modulated signal transmitted from the second electromagnetic resonance coupler; a third rectifier circuit that generates charging voltage by rectifying a second radio-frequency wave isolatedly transmitted by one of the plurality of electromagnetic resonance couplers; a capacitor that charges a charge in accordance with the charging voltage; and an output circuit which selects whether or not to supply the charge charged in the capacitor to a gate terminal of a semiconductor switch, in accordance with at least one of the first signal and the second signal.