| 摘要 |
1289930 Crystal oscillators; bi-stable circuits ITT INDUSTRIES Inc 8 July 1971 [15 July 1970] 32163/71 Heading H3T In a circuit which may have a piezo.electric crystal connected between the emitters of two cross-coupled transistors T 1 , T 2 , to provide an oscillator the two transistors have their emitters connected via a collector emitter path of a respective transistor T 5 , T 6 of like polarity to an earth line, their collectors connected via the, collector-emitter path of a respective transistor T 3 , T 4 of opposite polarity to a supply line and their bases connected to the base of the respective transistor T 3 , T 4 , a constant potential being applied to the paralleled bases of transistors T 5 , T 6 . An emitter follower output stage comprising transistor T 7 with emitter load T 8 as shown may be added and the constant potential be supplied by resistor R and transistor T 9 functioning as a diode. A Zener diode may be used in place of T 9 . The circuit may be monolithically integrated and when connected to an external crystal and appropriate frequency dividers be used to drive a clock or provide a stable oscillator &c. |
