ATA5278_06 ATMEL [ATMEL Corporation], ATA5278_06 Datasheet - Page 14

• Manufacturer Part Number: ATA5278_06
• Description: Stand-alone Antenna Driver
• Manufacturer: ATMEL [ATMEL Corporation]

Figure 3-9.
Figure 3-10. LF Data Modulation with PSK
14
ATA5278
MODACTIVE pin
MODACTIVE pin
LF Data Modulation with ASK
Driver control
Driver control
Driver control
Driver control
Resulting
Resulting
antenna
antenna
Half bit
Half bit
values
values
signal
signal
signal
signal
input
input
The LF data stream in
get this result, a hex value of 0F6h has to be written into the data buffer via the SPI. The time
value t
configuration register 2. Note that the MODACTIVE pin is active even if the half bit at the modu-
lator stage is “0”.
In PSK mode (NASK_PSK = 1), the phase of the carrier signal is shifted by 180° on any change
of the LF data in the buffer. Taking the same data sequence as in the previous example, the dia-
gram changes shown in
X
X
Start of modulation
Start of modulation
Bitrate
t
t
Bitlength
Bitlength
0
0
is the period of one logical bit, which is defined by the selected data baud rate in
/2
/2
t
t
Bitlength
Bitlength
1
1
Figure 3-9
Figure
1
1
3-10.
has a length of four logical bits and therefore eight half bits. To
0
0
1
1
1
1
1
1
End of modulation
End of modulation
1
1
X
X
4832C–RKE–02/06