323 / | HD | ELECTRICITY: POWER SUPPLY OR REGULATION SYSTEMS |
234 | DF | OUTPUT LEVEL RESPONSIVE {6} |
265 | DF | .~ Using a three or more terminal semiconductive device as the final control device {5} |
282 | DF | .~.~ Switched (e.g., switching regulators) {6} |
284 | .~.~.~ With threshold detection |