I have a H-bridge based on FAN7392 drivers. This bridge works at 350VDC to output a approximately 240V 50Hz waveform. This circuit is isolated from rest of the board and I would like to maintain the isolation. The bridge is fed by two complementary PWM signals from a microcontroller. The signals can be isolated easily with opto-couplers - however I'm worried that the timing difference between the opto-isolators might cause one side of the bridge to turn on both it's transistors simultaneously, for a short time. For instance, if one opto-coupler takes 2us to go high while the other takes 3us to go low there will be a 1us interval where one half of the bridge will be short-circuiting the power supply.
So my main question is, what is the best way to isolated timing critical signals?