| 摘要 |
1,245,612. Piecewise linear function generators. WESTINGHOUSE ELECTRIC CORP. 1 Oct., 1968 [17 Oct., 1967], No. 46571/68. Heading G4G. A function generator comprises a switched feedback network (Fig. 2) wherein plural operational amplifier stages OA 1 to OA 3 may provide direct positive feedback or be inverted to provide negative feedback to the summing junction # in with the input E in . At the inputs of the operational amplifiers the output voltage E out and a bias voltage are combined through summation resistors at points # 1 to # 3 , and the amplifiers have feedback over blocking diodes D 11 to D 31 and in parallel therewith series diode and resistor circuits D 12 , R 14 to D 32 , R 34 ; the outputs from the diode resistance junctions of selected amplifiers being connected over summation resistors to input # 5 of a feedback inverter amplifier OA 5 feeding the summation point # in , while other selected amplifiers similarly feed the summation point over summation resistors without inversion. The series diode resistor circuits in conjunction with the bias sources operate as selective switches responsive to output signal amplitude, and the latter varies with input voltage according to the piecewise linear synthesis of a required function with bias determined break points (Fig. 3, not shown). Any desired number of stages having negative or positive feedback may be utilized and diode and bias polarities may be selected as required. |
