Abstract:

A signal source capable of adjustable sinusoidal and square waves with stable range and reliable precision is designed based on the DDS with a single-chip as the control.The elliptic filter is used to remove the high frequency noise and stabilize the signal at the output,and the B-free power amplifier circuit to improve system load capacity.The hardware circuits are described and tested.The peak-to-peak value is continuously adjustable 0~20 V on a load of 50 Ω.The system has the advantages of simple circuit,powerful functions and good expandability.

Key words: DDS;elliptic filter;B-free power amplifier circuit