Signal distortion for common power supply

[yokel]

I am using two PWM amplifiers for amplifying two PWM signals which are 90degree out of phase. Both the amplifiers are run from the same dc power source and common ground. I am providing the PWM signals from function generator.

Now the problem is- in the output end the rising and falling of one signal is distorting the shape of another signal and vice versa. Can anyone tell me the probable reasons and how I can solve this problem.

thanks a lot in advance

[Hero999]

It sounds like the resistance and possibly the inductance of the power supply leads is too high.

The question is does it really matter?

If it's driving a MOSFET or an inductor in an SMPS and there's a 100mV glitch on a 10V waveform it shouldn't matter.

Anyway you haven't provided enough information, please post a schematic.