LRI512 datasheet(3/54 Pages) STMICROELECTRONICS

3 / 54 page

3/54

LRI512

Commands

The LRI512 supports the following commands:

–

INVENTORY: used to perform the anti-collision

sequence.

–

STAY QUIET: to put the LRI512 in quiet mode.

The LRI512 is then deselected and does not re-

spond to any command.

–

SELECT: used to select the LRI512. After this

command, the LRI512 processes all READ/

WRITE commands with the Select_Flag set.

–

RESET TO READY: to put the LRI512 in the

ready state.

–

READ BLOCK: to output the 32 bits of the se-

lected block and its locking status.

–

WRITE BLOCK: to write the 32-bit value in the

selected block, provided that it is not locked.

–

LOCK BLOCK: to lock the selected block. After

this command, the block cannot be modified.

–

WRITE AFI: to write the 8-bit value in the AFI

–

LOCK AFI: to lock the AFI register.

–

ACTIVATE EAS: to set the non volatile EAS bit.

When the EAS bit is set, the LRI512 answers to

the POOL EAS command.

–

DEACTIVATE EAS: to reset the non volatile

EAS bit, so that the LRI512 no longer answers

to the POOL EAS command.

–

POOL EAS: used to request all LRI512s in the

Reader field to generate the EAS signal, provid-

ed that their EAS bit is set.

Initial Dialogue for Vicinity Cards

The dialogue between the Vicinity Coupling De-

vice (VCD) and the Vicinity Integrated Circuit Card

(LRI512) is conducted through the following con-

secutive operations:

– activation of the LRI512 by the RF operating

field of the VCD.

– transmission of a command by the VCD.

– transmission of a response by the LRI512.

These operations use the RF power transfer and

communication signal interface specified in the fol-

lowing paragraphs. This technique is called Read-

er Talk First (RTF).

Power Transfer

Power transfer to the LRI512 is accomplished by

radio frequency at 13.56 MHz via coupling anten-

nas in the LRI512 and in the VCD. The RF operat-

ing field of the VCD is transformed on the LRI512

antenna as an AC voltage which is re-dressed, fil-

tered and internally regulated. The amplitude

modulation (ASK) on this received signal is de-

modulated by the ASK demodulator.

Frequency

The ISO15693 standard defines the carrier fre-

quency

(

fc)

the

operating

field

13.56 MHz ± 7 kHz.

Operating Field

The LRI512 operates continuously between Hmin

and Hmax.

– The minimum operating field is Hmin and has a

value of 150 mA/m rms.

– The maximum operating field is Hmax and has a

value of 5 A/m rms.

A VCD shall generate a field of at least Hmin and

not exceeding Hmax in the operating volume.

LRI512 数据表(PDF) 3 Page - STMicroelectronics

LRI512 数据表(HTML) 3 Page - STMicroelectronics

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54

数据表下载