Atmel ATA5283 - Manual (Page 7)

7
4598H–AUTO–03/07
ATA5283
3.8 Standby Listen Mode
In the standby listen mode the IC monitors the coil input with a very low current consumption.
The automatic gain control is switched off and the gain is set to the maximum value. The
N_DATA and the N_WAKEUP output are set to a high level.
Before the controller enters its standby mode after the communication, it should activate the
standby listen mode of the ATA5283 with a reset signal. This measure ensures that the IC
enters the power saving standby mode and that the IC wakes the controller correctly with the
next preamble signal.
3.9 Applications
Figure 3-6 shows a typical TPM application of the ATA5283. Combined with the antenna reso-
nant circuit the ATA5283 is used as wake-up receiver for the microcontroller and the connected
temperature- and pressure-sensor.
Note: To avoid supply voltage ripples to affect the microcontroller, an RC filter (R1 = 100
Ω
, C1 = 10 nF)
is recommended.
Figure 3-6. Application
5
7
6
1
RESET
R1
LA CA
433 kHz
125 kHz
C1
Central
board
controller
T5743
UHF Rx
UHF Tx
Antenna
driver
ATA5275
Micro
controller
N_WAKEUP
N_DATA
Vref
Temp.
sensor
Pressure
sensor
2
3
8
4
ATA5283
ATAR862
Amplifier
with
AGC