Methods and apparatus to transmit signals in isolated gate drivers

A signal converter comprising:

• a first encoder including a first input coupled to an output of a signal generator, a second input coupled to an output of a first sensor, an output, and a first multiplexer, the first input of the first encoder corresponding to an input of the first multiplexer, the output of the first encoder corresponding to an output of the first multiplexer, the first encoder configured to:
• transmit a first signal at the output of the first encoder, the first signal including a first voltage level and a first frequency;
• in response to a first indication by the first sensor, transmit a second signal at the output of the first encoder, the second signal including a second voltage level and a second frequency, the second frequency different than the first frequency;
• and
• a second encoder including a first input coupled to the output of the first encoder, a second input coupled to a second sensor, a second multiplexer, and an output, the first input of the second encoder corresponding to an input of the second multiplexer, the output of second encoder coupled to an input of a modulator, the output of the second encoder corresponding to an output of the second multiplexer, the second encoder configured to, in response to a second indication by the second sensor, transmit a third signal to the modulator, the third signal including a third voltage level different than the first voltage level and the second voltage level.

A system comprising:

• a switch including a first current terminal coupled to a voltage supply and a second current terminal coupled to a reference node, the switch configured to conduct current from the first current terminal to the second current terminal;
• a signal generator including an output;
• a first sensor including an output and an input coupled to the first current terminal of the switch;
• a second sensor including an output;
• a modulator including an input and an output;
• a capacitor including an output and an input coupled to the output of the modulator;
• and
• a signal converter including an output coupled to the input of the modulator, a first input coupled to the output of the signal generator, a second input coupled to the output of the first sensor, and a third input coupled to the output of the second sensor, the signal converter configured to:
• transmit a first signal, the first signal including a first voltage level and a first frequency;
• in response to a first indication by the first sensor, transmit a second signal, the second signal including a second voltage level and a second frequency, the second frequency different than the first frequency;
• and
• in response to a second indication by the second sensor, transmit a third signal, the third signal including a third voltage level different than the first voltage level and the second voltage level.