Power consumption considerations

AN3433

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Doc ID 019046 Rev 2

pulses emitted. This value must be adjusted initially in the application environment to obtain

the best measurement stability.

Increasing the SwingsCnt value improves DAC accuracy, but also increases the power

consumption of the RF drivers (pin VPS_TX).

When using the CR95HF or STRFNFCA demoboard, we recommend a SwingsCnt value of

0x3F. This value corresponds to 64 RF pulses per burst (in blue) for a duration of 4.7 µs as

shown in Figure 6. This results in a mean power consumption of 100 µA.

Figure 6.

RF burst in Tag Detection mode

1.

In the above figure, yellow represents the 27.12-MHz (HFO) oscillator and the RF emission is in green.