a switching circuit that transitions using a switch transistor . during the initial stages of a high - low transition , a control loop provides supplemental pre - charge to the gate of the switch transistor to reduce high - low switching delays . once the current flowing through the switch transistor rises to a level causing the output voltage to change at specified speed threshold , a loop opening mechanism opens the loop . further opening of the switch transistor in the high - low transition is taken care of by a relatively constant current source . at that point , no or negligible feedback current is used to charge the gate of the switch transistor . low - high transitions may be performed in a similar complementary manner .