High side signal interface in a power converter

A resonant power converter, comprising:

• a high side switch coupled to receive an input voltage at one end of the high side switch;
• a low side switch coupled to an input return at one end of the low side switch, wherein an other end of the low side switch is coupled to an other end of the high side switch at a half bridge node, wherein a voltage of the half bridge node resonates between a ground reference and the input voltage;
• a tank circuit coupled to the high side switch and the low side switch at the half bridge node;
• an energy transfer element coupled to the tank circuit to transfer energy from an input of the resonant power converter to an output of the power converter in response to switching of the high side switch and the low side switch;
• and
• a controller coupled to control switching of the high side switch and the low side switch in response to a feedback signal representative of the output of the resonant power converter, wherein the controller includes:
• a control circuit is coupled to generate a low side drive signal in response to the feedback signal to control switching of the low side switch, wherein the control circuit is further coupled to generate an ON signal and an OFF signal in response to the feedback signal;
• and
• a high side signal interface circuit coupled to receive the ON signal and the OFF signal and coupled to reject common mode signals caused by a half bridge slew, wherein the high side signal interface circuit is coupled to generate a high side drive signal in response to the ON signal and the OFF signal to control switching of the high side switch, wherein the ON signal and the OFF signal are coupled to be pulled up in response to a bypass voltage during an initial state, wherein the high side signal is coupled to turn on the high side switch in response to the control circuit pulling the ON signal low, and wherein the high side signal is coupled to turn off the high side switch in response to the control circuit pulling the OFF signal low, wherein the high side signal interface circuit comprises:
• a common mode cancellation circuit coupled to generate a first current signal, a second current signal, a third current signal, a fourth current signal, and a common mode rejection signal in response to the ON signal, the OFF signal, and the bypass voltage;
• a first current hysteresis comparator coupled to generate a first output signal in response to the first current signal, the fourth current signal, the common mode rejection signal, and the high side drive signal;
• a second current hysteresis comparator coupled to generate a second output signal in response to the second current signal, the third current signal, the common mode rejection signal, and the high side drive signal;
• and
• a first latch coupled to generate the high side drive signal in response to the first and second output signals.