RF generation help

[saurabh17g]

Hello,
I want to design a circuit which generates a frequency from 1Hz to 20MHz.
amplitude should be 5V p-p.
Moreover the device should have a keypad and LCD interface.
The frequency set by keypad should be outputted by the circuit.
I tried a lot of options using various ICs like AD9833 and other AD ICs. But the current requirement is not sufficient. So please suggest me some thing

 

[NickS]

What are the extent of your electronics abilities?

I would approach this task as you specified with the following bare minimum circuits.
1) Power management: Regulate input power to at least 2 probably more rails
5v for output driver, 3.3v for logic, perhaps 12v for keypad or display
2) Microcontroller to interface the keypad, display and DDS (not all that trivial)
3) Supporting circuitry for the display
4) Supporting circuitry for the keypad
5) Supporting circuitry for the DDS
6) Output amplifier/driver