Configuration of TX Inputs for MAX2830

The MAX2830 has a LPF in the TX path and HPF/DC Offset Correction in the RX path. The TX should have no issues handling signals in the audio range, but the RX path HPF has a 100 Hz corner frequency, which will attenuate signals in said range.

Even if the TX/RX paths could handle those frequencies, I do not recommend using the MAX2830 for this application, as it is intended/optimized for use with the 802.11 standard. Any audio signal you feed to this part may end up distorted as a result.

For DSBSC, you can tie your differential audio to the I pins, but you have to ensure that you meet the input common-mode voltage requirements of the part. The MAX2830 asks for 0.9V to 1.3V. This also means that you cannot directly tie Q to ground. You should instead provide a DC bias to the pins and decouple to ground.

The distortion I mention can come from DC offset voltage between the I and Q inputs, input bias mismatch, as well as internal offsets from the mixer and amplifiers.

This distortion will decrease carrier suppression. It may negatively affect the audio quality as well. As it is, the part can handle the signals that you will input on the TX pins, but you would need to test in lab to verify it works as you want it to.

Hi Klayton,

Are you all set with your inquiry?

Best,

Joe

Closing this thread due to lack of activity.