Hello,

I made a simulation circuit that would amplifier the AC voltage out of the DDS AD9850 from .3v pk-pk to 12v pk-pk. Works fine on simulator, but when I put All the parts together, I am far from the simulation. Bascially I dont get any output .
I used a waveform generator as the input to debug the circuit, and I start to get output when I increase the input amplitude to over 2v pk-pk. even then I get only half the impulses and they are much shorter .
See attched. any help is welcome

ken
Mod: rotated image 180deg

 

hi cap,
Is one lead of the SigGen input at ground, ie; the same ground as the 15v power supply.?
E

 

Lets say you will use 50 ohm cables for Z in and out of the amp. The simulation would include the impedance network.
A wide band op amp such as the CLC404 data sheet would most likely have an example if not it should have impedance over frequency characteristic curves that would show where you are with AD9850, however you may want to take the raw signal from output pin and feed it through a 5 pole.

 

Hello,

I made a simulation circuit that would amplifier the AC voltage out of the DDS AD9850 from .3v pk-pk to 12v pk-pk. Works fine on simulator, but when I put All the parts together, I am far from the simulation. Bascially I dont get any output .
I used a waveform generator as the input to debug the circuit, and I start to get output when I increase the input amplitude to over 2v pk-pk. even then I get only half the impulses and they are much shorter .
See attched. any help is welcome

ken
Mod: rotated image 180deg

the signal generator ground is going to the 6 volt, just like the diagram.
I tested with my circuit (ad9850) also, but the input signal I guess is too weak to amplify, I dont get anything at the output