AWR2243: LO Power

Frank

Prodigy 70 points

Part Number: AWR2243

Hi,

As the pic shows, the typical output power of 20GHz LO signal is 7dBm, but i'm confused about the min and max power,

1. 3~10dBm, why the difference is so big ?

2. Is there an automatic controller to adjust the output power according to the SYNC IN signal ?

3. If there is no automatic controller, when the output power is 10 dBm, and the loss is smaller than 3dB, then the input power is bigger than 7dBm, what will happen ?

Thank you very much !

over 2 years ago

0 Vivek Dham over 2 years ago

TI__Guru 58035 points

Hello Frank,

The 20Ghz output signal power varies with temperature and process. Hence the variation of 3 -10 dBm.

There is no closed loop control of this power level, since accurate power level is not really important here. Just the minimal signal levels needs to be guaranteed at the SYNC IN pins. So you in your analyses you can use the min SYNC OUT level for your system estimation.

Theoretically it could happen that you get 10dBm SYNC OUT power and incase you have less than 3dB loss on the PCB , then the SYNC IN level is > 7dBm. But its easy to have 3dB loss on the PCB for a 20Ghz signal. So typically that is not an issue, mostly ensuring the loss is small enough to ensure the min level is the challenge.

Regards,
vivek

0 Frank over 2 years ago in reply to Vivek Dham

Prodigy 70 points

Hi vivek,

Thanks for your reply!

I have no idea about the loss of 20GHz signal, do you have any measured data ?

Regards,
Frank

0 Vivek Dham over 2 years ago in reply to Frank

TI__Guru 58035 points

Hello Frank,

The loss of the 20Ghz signal would depend on your PCB design. This is the loss in the trace used to connect the SYNC OUT to the SYNC IN .

regards,
vivek

0 Frank over 2 years ago in reply to Vivek Dham

Prodigy 70 points

Hi vivek,

Thanks for your reply!

I see, I can get the simulated loss using HFSS, but i'm confused about the difference between simulation and test.

so, the experience in test can be helpful.

Regards,
Frank

+1 Vivek Dham over 2 years ago in reply to Frank

TI__Guru 58035 points

Hello Frank,

There is no each way to test this. You could think of using our internal monitors which provide the measured 20Ghz signal levels at SYNC OUT and SYNC IN pins. This could provide you a rough estimate of the signal losses externally.

regards,

vivek

0 Frank over 2 years ago in reply to Vivek Dham

Prodigy 70 points

Hi vivek,

I see. Thanks for your reply!

Regards,

Frank

0 Frank over 2 years ago in reply to Vivek Dham

Prodigy 70 points

Hi vivek,

I cannot find the monitoring and diagnostic mechanisms about the 20GHz signal from the 2243 docs.

Can you provide some recommendation?

Regards,
Frank

+1 Vivek Dham over 2 years ago in reply to Frank

TI__Guru 58035 points

Hello Frank,

In the Interface Control Document, which is part of the mmwave DFP (www.ti.com/.../MMWAVE-DFP ) you can find details of the " AWR_MONITOR_PMCLKLO_INTERNAL_ANALOG_ SIGNALS_CONF_SB" monitoring API. This includes the 20Ghz CLK monitoring.

Regards,

vivek..

0 Frank over 2 years ago in reply to Vivek Dham

Prodigy 70 points

Hi vivek,

I see. Thanks for your reply!

Regards,

Frank

Sensors

Sensors forum

AWR2243: LO Power