DS00795A-page 11

© 2002 Microchip Technology, Inc.

AN795

WIDE FREQUENCY RANGE PULSE GENERATOR

The TC9400 V/F converter is useful in the laboratory as a portable, battery-operated, low-cost frequency source. The TC9400

provides both pulse and square-wave outputs. By adding an op-amp integrator, a triangular waveform can also be generated. The

outputs can be frequency-modulated via the FM input.

FREQUENCY MULTIPLIER/DIVIDER WITH INFINITE RESOLUTION

Frequency scaling can easily be performed by first converting the incoming frequency into a proportional DC voltage. This is

accomplished by using the TC9400 in the F/V mode. Once the frequency is in a voltage format, it is easy to scale this voltage up or

down by use of a single potentiometer. The resultant voltage is then applied to a TC9400 V/F converter, which generates a

proportional output frequency.

FIGURE 23: Wide frequency range pulse generator.

FIGURE 24: Frequency multiplier/divider with infinite resolution.

TC9400

V/F

FM

Input

Frequency

Adjust

Op

Amp

+

–

TC9400

V/F

TC9400

F/V

)