WL1837MOD: Deviation from maximum rated TX power limits

Hi Colombo,

Is the latest FW version being used? The latest, WL1837MOD_INI_FCC_CE.ini, can be downloaded from here.

Is RTTT being used to transmit and measure output power?

Has the customer's board design been reviewed? A design review can be requested from here.

BR,

Seong

Hi Seong, 

yes, we are using latest FW version and device configuration WL1837MOD_INI_FCC_CE.ini.

We are performing "conductive power measurements" from the pins of device and in attachmment you can find the output. 

Are the "max rated power" (column J in SISO tabs and M,N in MIMO tab) are the expected values ? 

For the test we followed the "swru562" user guide and in attachment an example of test configuration. 

In test mode is the "PerSubBandTxTraceLoss" evaluated or not ?

BR

Carlo

Carlo,

I will look into this and get back to you soon.

BR,

Seong

Dear Seong, 

I need urgently feeback from you about this topic. 

Did you have a look at the data (file in attachment) ? 

Is it correct the maximum rated power expected for each test case ?

Why did we face so big deviation from expected data ?

In test mode is the "PerSubBandTxTraceLoss" evaluated or not ?

Thanks and regards, 002 EXOR X5 CE SAR - WiFi - 13304888 CPM Sheet V5.0 - 090221.xlsx.zip

Stefano

Hi Stefano,

Our released. INI file should be used for all the antenna listed and the PerSubBandTraceLoss not modified. If you, for example increase this value, it will force the internal PA to drive harder, which in turn may cause additional issue in passing regulator certification. The values in the .INI file have been optimized for performance and margin to the requirements.

Has the customer's design been reviewed?

How many boards have been tested?

BR,

Seong

Hi Seong, 

As I already wrote in my previous post, we used released .INI file without any modification.

The first point I would like to know is the expected "max rated power" for each test configuration I reported in the file in attachment. 

From TI documentation I don't really know if those values are correct or not.

• Could you please review this file and confirm ?
• What is the expected "max rated power" from each antenna in MIMO configuration ?
• Is "PerSubBandTraceLoss" evaluated in test_mode configuration (ref. swru562) ?

Thank you very much for your support. 

These information are really urgent to complete SAR test. 

BR, 

Stefano

8156.002 EXOR X5 CE SAR - WiFi - 13304888 CPM Sheet V5.0 - 090221.xlsx.zip

Stefano,

The comment on the INI file was in response to the question regarding PerSubBandTraceLoss. 

I have been unable to get to the lab all week to make these measurements myself due to the weather in Dallas, so I apologize for the delay. 

I will ask R&D if they have this data in the meantime.

Has the customer's design been reviewed? How many boards have been tested?

BR,

Seong

Hi Seong, 

we had internal review, not from TI, and design check list was fulfilled.

The behaviour is common to all samples. 

Consider that we are evaluating conductive power measurements and that we are working on device pin. 

The first thing we want to know is the expected "max rate power" for test configuration. Maybe we are using wrong reference values. 

After that we want to know how to evaluate MIMO configuration with respect "max rate power" from each antenna. 

BR,

Stefano

Stefano,

I am still waiting for R&D to respond back with the expected "max rate power". I will get back to you as soon as I hear back from them.

BR,

Seong

Hi Stefano,

Apologies for the delay. I've still yet to hear back from R&D.

First I want to point out that RF_ANT2 is MIMO only. 

I will have time tomorrow to go to the lab and compare data with the customer's spreadsheet. I'll let you know the results.

BR,

Seong

Hi Seong, 

it's OK. 

Please get my email : stefano.dacomo@exorint.com.

Thanks a lot. 

BR,

Stefano