Hi,
I've got a TRF7970A EVK board connected to a coil through the SMA connector, and I am using the RSSI level in Reg0x0F to evaluate coil read range. I've placed an RFID tag in the centre of the coil and I am monitoring the RSSI level.
When running at Full power, my Main and Aux RX strength are 5 and 0 respectively. Using Half power, my Main and Aux RX strength are both 5.
This seems counter-intuitive, so what else is going on?
I guess that if my coil is does not have a characteristic impedance of 50ohms, then the 4-50ohm impedance matching circuit will behave differently - giving an overall better power transfer when the output impedance is 8ohms? What do you guys think?
Stephen
