15
4857C–AUTO–07/06
ATAK5276-83
To reach the current regulation level of 1.5 Ap (see
), the series resistor RANT (R1) on
the antenna module has to be shorted. In this case, the antenna quality factor is increased to
Q = 108. Due to the high Q-factor, the current regulation leads to a short overswing during the
switch-on phase. In the shorted R1 state, the antenna can also be operated with half current
0.75 Ap by opening jumper J3 (RCR = RCR1 = 100 k
Ω
).
Figure 6-7.
Antenna Current in Regulation
Note:
Consider the power dissipation of shunt resistor RSEN and module resistor RANT when operating
the driver continuously (loop operation mode).
When operating the driver out of current regulation, the PWM stage is controlled by a 1:1 duty
cycle. This could be an advantage with respect to the radiated harmonics in contrast to using
regulation mode.
6.4
Signal Transmission Measurements
The relationship of the sent and received protocol can be measured on the boards ATAB5276
(transmitter) and ATAB5283 (receiver) via the related test pins TPx.
shows an example of the send protocol with the default data pattern and the default transmitter
current of 0.6 Ap.
