Hello,
I am testing the TQP9111-PCB2600 evaluation board. The initial results look good, however I am finding a few performance metrics not aligning with datasheet parameters.
These are my test conditions:
• Input frequency= 2394MHz, CW
• Vcc and Vaped = 5V
I determined that the output P1dB is about 31.8dBm while total current draw is almost 1A, which is almost twice as much as the 545mA Total Current parameter in the datasheet. Actually without any RF input signal, the total current draw is already 560mA @ 5V Vcc=Vpd.
My questions are:
- Do my measurements/observations make sense?
- Does the evaluation board require tuning in order to achieve the datasheet parameter?
Thank you,
The current specified in the datasheet of 545mA typical is quiescent, so with no RF signal applied. Below is a plot of typical current vs output power for the TQP9111 2140MHz eval board which should give you a good idea what to expect. Current of 1Amp at 31.8dBm seems reasonable. The P1dB you measure seems slightly low. As you are testing CW it is worth cooling the board as if the device is getting hot the P1dB will drop. Once you take into account temperature, PCB loss and part-part variation then your results are probably OK. Worth checking all your calibrations are correct for cable losses. You should not need to tune the board.
Hello Chris_LS, thank you for confirming the current draw, and confirming that the board should not need tuning to get the expected output P1dB. Hopefully on the prototype we designed, it will not need tuning. I will also re-check my input and output calibrations, and pay attention to keeping the circuit cool.
Speaking of the prototype we designed, other than the 50-ohm transmission lines at the input and output, are there any other sections of critical trace dimensions? Do the bias feedpoints at pins 16, 18 and 20 need to be certain impedance and electrical lengths? How about the sections immediately at the signal in and out? I am attaching a screenshot highlighting the sections of concern (see red circles).
My prototype board has very low output power: about +23dBm with an input of +3dBm. Hence I am confirming performance of the evaluation circuit as a start to the debugging.
Thank you in advance for your input.
The position of all tuning components on the RF input and output is critical, the line lengths form part of the matching. The same goes for the position of L1 and L2 and associated decoupling, but these are not quite so important.
If your own PCB uses a different dielectric and board height to the Qorvo eval board you would need to scale the distances. This is to maintain the same electrical length at the frequency of interest.
If you need any more detailed support with the tuning then please contact appsupport@qorvo.com stating your company name and location.
Thank you for the important details.
I tried to contact appsupport@qorvo.com but the email bounced back. It got blocked. Here is the message received back:
The response from the remote server was:
554 5.7.5 Permanent error evaluating DMARC policy
Any reason why that is? I did state my company name and city+country in the email.
DMARC is an e-mail security protocol, so probably something to do with your e-mail DNS and set-up.
