| 摘要 |
<p>PURPOSE:To rise an output current at a high speed by feeding back positively a part of an output current to a time constant capacitor connected to a source of an FET in an on-delay delay circuit. CONSTITUTION:In turning on a switch 9, an N-FET-1 is turned on, a capacitor 4 is charged through a resistor 5 and an FET1 and the source potential of the FET1 rises. When the source potential approaches the gate potential after a prescribed time, the internal impedance of the FET starts increasing and when the drain potential breaks down a Zener diode 6, a base current of a transistor (TR) 7 flows and the TR7 is turned on. Its emitter current flows to the capacitor 4 at the same time and increases the internal imp-edance of the FET1, then the emitter current is arisen at a high speed by the positive feedback action.</p> |
