Output of IQ from TRF371135

JS:

If you are getting DC + BB then that sounds accurate.  The output common mode voltage is 1.5V.  You should see your signal operating around this common mode voltage.

A couple of other hints.  0 dBm is likely too strong an input signal for the device.  I recommend to back off to -10dBm or less.

The '11 cannot drive 50 ohms.  If you drive 50 ohms directly then you will see distorted output.  If you are using the on-board transformers then you can drive into 50 ohm test equipment.

--RJH

J: Use "Rich Text Formatting".  There should be a button in the corner to select.  That brings up a menu pane and allows you to attach a file.  -RJH

Hi RJH

I am attaching the snapshot of IQ with canstillation.

If i see the canstillation it should not come like this.

Regards

J S Hyanki

J:

I agree that the screen shots look distorted.  What frequency is output BB signal at?  I assume that you are using a high impedance probe on the scope.  If so, I recommend probing before the transformers at J3, J4, J8, J13.  You can remove the jumpers at W4-W7.  Set the BB frequency to be something around 1 MHz.  This would be setting LO at say 2.4 GHz and RF input at 2.401 GHz.  Monitor the current that the EVM consumes.  Nominal should be around 368 mA on 5V.  If you see it considerably higher, that indicates the outputs are being loaded down too much (usually with too low output impedance).