| 摘要 |
1,248,668. Automatic voltage regulation. TEXACO DEVELOPMENT CORP. July 23, 1969, No.36933/69. Heading G3X. A D.C. voltage V 2 is maintained constant irrespective of variations of input voltage and/or load and/or temperature by the circuit shown, which comprises two operational amplifiers 10, 12 respectively receiving the input voltage and providing the output voltage V 2 , and four feedback loops consisting of a Zener diode 16 in parallel with the amplifier 10, fixed and variable resistors 32, 34 in parallel with the amplifier 12, a resistor 52 connected between the output of amplifier 12 and the input of amplifier 10 and a resistor 22 also connected between this output and input. The circuit parameters are chosen so that the overall gain of the cascaded amplifiers 10, 12 is approximately unity whilst the Zener current is maintained to provide a stable voltage for reducing the effect of the offset voltages of the amplifiers, of which the amplifier 12 is preferably transistorized to improve temperature stability. Since the regulator has two stable states, a resistor 30 is provided to ensure stabilization in the correct state when power is first turned on. A discussion is given of the choice of the various circuit components, of the adjustment of certain of them and of the mathematical basis of the circuit operation. |
