ATA5275 ATMEL Corporation, ATA5275 Datasheet - Page 5

• Manufacturer Part Number: ATA5275
• Description: Integrated 1.5 A peak current BCDMOS antenna driver IC dedicated as a 125 kHz wake-up channel transmitter for TPM applications
• Manufacturer: ATMEL Corporation

Transmission Mode
ASK Modulation
Anti-bouncing Filter in
Transmission Mode
Time Out and Time Out Reset
4739B–AUTO–10/04
For the transmission of a wake-up signal or data to a receiver, the ATA5275 generates a
antenna resonance synchronized signal at the antenna driver output (DRV pin). A con-
nected LC antenna radiates a magnetic field. For the data transmission the field can be
100% amplitude modulated by the DIO interface input. If a low level signal is applied at
the DIO pin, the driver generates a square wave signal DRV for the antenna. If a high
level signal is applied at the DIO pin the driver is stopped and switched to ground. In this
way ASK modulated data can be transmitted (see Figure 6).
Figure 6. Data Transmission
The DIO input signal is delayed for a anti-bouncing time.
The driver is switched on after a delay time of T
a low level continuously. The driver is switched-off after a delay time of T
pulled to high level.
The T
bance pulses from the DIO Line.
Figure 7. Anti-bouncing
The IC has a time out supervisor for the interface line to avoid unintended continuous
transmission in case of line errors. The time out timer runs if the DIO pin is pulled to a
low level. If the DIO pin is permanently low for more than the time T
switched off and the IC enters the standby mode. This avoids the discharging of the sup-
ply battery if the DIO line has a failure like a body contact or another permanent low
level failure. The time T
COIL
DRV
DH
DIO
time depends on the antenna resonance frequency, suppressing short distur-
OUTL
depends on the antenna resonance frequency.
TD_L
ATA5275 [Preliminary]
DL
(typically 64 µs) if the DIO is pulled to
TD_H
OUTL
DH
the driver is
if the DIO is
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