P4069 EM Microelectronic, P4069 Datasheet - Page 10

• Manufacturer Part Number: P4069
• Description: 128 Bit Read/write Contactless Identification Device With Otp Function
• Manufacturer: EM Microelectronic

The modulation envelope of the magnetic field induced by the reader is observed by the P4069 as shown in the
following figure.
Comment to above timings:
t
t
t
Refer to table 4 for timings range.
In the above example, the Read ROM command (1010 0101) is sent.
After successful 8-bit command detection, the P4069 will output continuously the ROM contents.
Reset, Read ROM and Read Configuration Word
commands
After detecting these commands the IC returns in
read mode and starts reading corresponding block
(EEPROM or ROM).
Write Word
commands
For Write commands, a total of 32 significant bits
have to be transferred from reader to P4069. The 32
bits are transferred in a sequence of 4 bytes. Each
byte is headed with start bit at logic 0 (as in normal 8-
bit command) and trailed with stop bit at logic 1. The
antenna sends an uninterrupted sequence of 40 bits
(32 command bits, 4 start bits and 4 stop bits).
This data organization ensures re-synchronization of
the P4069 with the reader signal, and avoids that
wrong data would be extracted due to missing or
spurious clocks from the clock-extractor of the IC.
The IC treats the Write command as follows:
S1
S2
S3
: at least one sample LOW. 2 bit periods + some security since the IC and R/W unit are not synchronized.
: one sample high to enter Command Processing state defines lower limit. Watchdog timer defines higher limit
: at least 4 samples of peak detector have to be HIGH. In worst case the distance between samples can be 2
bit periods.
Duration of 3 bit periods is suggested.
(8 bits periods)
for Power Supply level. So using shorter times than upper limit is advised.
suggested.
t
S1
Synchronization pattern
and
Modulation of Magnetic Field
EM MICROELECTRONIC-MARIN SA
Please note that during this time the Modulator load is permanently on so this is the worst case
Write
t
S2
Configuration
t
S3
SB
Word
B0
B1
First byte received is treated in the same way as for
an 8-bit command. In the case that the processing of
the first byte detects a Write Word command, it first
puts the modulator load OFF for 1/2 bit period. During
this time, the antenna field is High (as stop bit is at
logic one) so the internal power supply capacitor can
be charged. Next the P4069 transitions to Start Bit
Detection State with modulator load ON and waits for
start bit at logic 0. The time out value is 2 t
out is reached before a start bit is detected, the IC
then returns to the read mode. Normally the start bit
comes already after 1 t
continues to process the next byte.
After the fourth byte has been detected, the P4069
verifies if the CRC check is OK and if the word, which
is addressed for writing, is not protected by the
configuration word. Next, power check is performed
to determine whether there is enough power available
to write EEPROM. This operation lasts 1.5-bit
periods. In the case all conditions above are fulfilled
(CRC, protection, power check) EEPROM is written.
If one of the conditions fails, the P4069 returns in
read mode without writing EEPROM.
t
B2
RDB
B3
B4
P4069/P4169
B5
Duration of 3 bit periods is
RDB
B6
and the P4069 then
B7
RDB
Figure 12
. If time
10