The 33pF handles amplifier loop phase, the diodes prevent input saturation effects, and "speed up" the switching process, since the amplifier never sees more than 0.7 V on its input.

Hi Steve,

Thanks for explaining the functioning of the 33pF capacitors and those diodes. But still those 22K and 20K resistor values are mystry to me.

Thanks & Regards,
Prahlad Purohit