Function Generator

This is a downright simple de- sign for an AF function gener- ator that supplies a rectangular and triangular signal, and can be fed from a single 9 V supply. The signal generator proper is a Type TLC272 dual CMOS opamp from Texas Instruments. This chip is remarkable for its low current consumption and wide operating range. The circuit is essentially com- posed of two functional parts. Opamp Al is connected to func- tion as a Schmitt-trigger whose toggle point is set to 4.5 V, while A2 is an integrator that converts the rectangular signal from Al into a triangular waveform. The oscillation frequency of the circuit is fixed solely by the ratio R/C and can be calculated from fo =122/4RR,C. Resistor R may be replaced by the combi- nation of the 10K resistor and 100K potentiometer as shown to R3 R1 A2 2mA 9V AAA 4V 110 100n effect continuous adjustment of the output frequency within the AF signal band. The generator should not be terminated in less than 10K. St 54 SUPPLEMENT R4 Al, A2...