| 摘要 |
PURPOSE: To effectively restrict a current flow to/from the output node of a circuit and to control the change speed of output voltage by providing each of two driving circuits in a compatible switching circuit consisting of a TTL logic circuit with a high voltage driver and a low voltage driver forming a Darlington pair. CONSTITUTION: A control ramp output cell 10 is formed by two driving circuits, a 1st high voltage driver includes transistors(TRs) Q6, Q7 forming a Darlington pair and connecting respective collectors to a high voltage souruce Vcc , through a resistor R7, the emitter of the TR Q6 is connected to the base of the TR Q7, and their node is connected to an earth through a resistor R6. A capacitor C1 is connected to the base of the TR Q6 and connected to the voltage source Vcc through a resistor R3. The low voltage driver to be a 2nd driving circuit includes TRs Q5, Q8 forming a Darlington pair, the emitter of the TR Q5 and the base of the TR Q8 are connected to the low voltage source (earth) through a resistor R5 and a Schottky diode D2. Either one of an output node and a capacitor C2 is connected to the collector of the TR Q8. |
