Hi Drauzio,

     There is no data for noise figure with EFR32MG chip. But it recommends to use the external LNA to improve the sensitivity, the sensitivity maybe 3-5dB improved according to your external LNA's noise figure.

     For the SAW usage, it recommends to use if there is strong interfere close to carrier. Please refer to the blocking performance of the chip to decide the SAW usage.

Regards,

Jun

Hi,

     You should connect it with setting  'Debug Mode' to Out. Please try to connect your customer board to BRD4001A with 10-pin mini simplicity debug connector for a try.

Regards,

Jun

You should connect these debug signals to P800 connector of BRD4001A, and power your custom board with external power supply since the pin1 of P800 is only for detect and not for power.

Regards,

Jun

Hi,

    It is possible damaged by EOS or ESD. Please contact your local FAE or sales man for further RMA analyse.

Regards,

Jun

Hi,

    I think you have connected your power pins to 3.3V correctly. The R1 can be removed since there is no need such strong pull-up resistor for reset signal. For the crystal, I am not sure you can add external 10pF capacitor to crystal. Usually the chip's internal capacitor bank can provide 7-12pF Cload to crystal, it doesn't need external capacitor if your crystal requires 7-12pF Cload. It can add external capacitor if the crystal requires > 12pF Cload.

    But I think the key point is that the SiM3xxxx debugger doesn't support EFR32 chips. I recommend you to use Silabs' BRD4001A mainboard to debug the EFR32 chips, it will use a 10-pin debug connector different from SiM3xxxx debugger, please refer to AN958 for more details:  https://www.silabs.com/documents/public/application-notes/an958-mcu-stk-wstk-guide.pdf .

Regards,

Jun

Hi Khan,

     As i know, there are 169MHz,390MHz, 434MHz, and 460-470MHz evaluation boards available for Si446x chips.

     For these demo boards, you can directly use them if your desired frequency is around +/-5% of fc. You should tune it to your desired operation frequency if it is out of +/- 10% of fc.

Regards,

Jun

Hi Steven,

     Yes, you can refer to BRD4258A for the matching circuits. But it can generate +20dBm output power with 100 to 125 ohms differential Rload at 3.3V power voltage level. But if you have a maximum 2.85V power supply, i think you can just get +18dBm to +19dBm output power, you can't get +20dBm output power in lower power voltage.

Regards,

Jun

Hi Khalid,

     Basically these modules have FCC certification IDs which registered in the regulation. You can directly cite them. For detail procedure, you can consult your local FCC test lab.

Regards,

Jun

Hi Mark,

     It is hard to connect such small semi-rigid RF cable to this PCB. As i consulted from module team, it said that the design should add some provisions for the cable. A 0ohm resistor between the RF output and the antenna input is useful, desoldering it that allows the cable center conductor to be soldered to either pin. The RF trace can also be looped out from under the module to the extent that it can be cut with a knife and scraped bare of the solder mask. If the PCB has a bit of extra area between the module and the board edge, with a ground plane on the top layer, it is possible to leave a mask opening for the antenna ground or to scrape away some of the mask to be able to solder the cable ground. The cable should then be bent such that it is perpendicular to the board edge with the module on it, to reduce its effects on the antenna.

     The following is the connection picture:

Regards,

Jun

Hello Matt,

       I think the CEL guy's comment is reasonable. For most RF device, its RF ports can handle 50V ESD voltage. This ESD voltage is a transient voltage which is far higher than the DC limit voltage.  So for the TVS selection, the TVS's break down voltage should locates between the peak RF voltage and the transient ESD voltage. And more you should choose a TVS for RF signal, otherwise the non-linear property of TVS may impact the RF performance.

Regards,

Jun