EMC Test question: Max electromagnetic power emitted by S210

[angel]

Hi Nordic,

Device: nRF51422. Protocol: ANT+. Softdevice: S210

We want to do the EMC test of our custom board and we would like to know at least an approximation of what is the emitted electromagnetic power in a normal application. We thought of measuring it by measuring power consumption of the device during communication, but it may not be the best way to know it.

Thanks!

[Jørn]

Hello angel

The nRF51422 has, according to page 51 of the product specification, a maximum RF output power (from the chip) of 4 dBm (2.5mW) and a minimum RF output power of -30 dBm (1uW).

If by electromagnetic power, you mean the poynting vector of the radiated electromagnetic field it would be dependent on the field radiated by your antenna in a given direction. You could make an approximation by calculating, or simulating, the radiated field from your antenna, and then use that to find the poynting vector. A more accurate approach would be to measure it in a test chamber.

If you mean unwanted EM radiation from the chip itself, that would be dynamic and dependent on what hardware is used at any given time. I'm afraid we don't have any specifics around the EMI from the chip that I am aware of.

I recommend you look at the white paper on RF Performance Test Guidelines and see if that can be of help. There are a couple of sections which might be relevant.

Best regards

Jørn Frøysa

[angel]

Thanks a lot Jorn!