SRI4K-A3T/1GE STMicroelectronics, SRI4K-A3T/1GE Datasheet - Page 5

• Manufacturer Part Number: SRI4K-A3T/1GE
• Manufacturer: STMicroelectronics

Specifications of SRI4K-A3T/1GE

• Operating Temperature (max): 85C
• Operating Temperature Classification: Commercial
• Lead Free Status / Rohs Status: Compliant

DATA TRANSFER
Input Data Transfer from the Reader to the
SRI4K (Request Frame)
The reader must generate a 13.56MHz sinusoidal
carrier frequency at its antenna, with enough ener-
gy to “remote-power” the memory. The energy re-
ceived at the SRI4K’s antenna is transformed into
a Supply Voltage by a regulator, and into data bits
Figure 4. 10% ASK Modulation of the Received Wave
Character Transmission Format for Request
Frame. The SRI4K transmits and receives data
bytes as 10-bit characters, with the least signifi-
cant bit (b
5.. Each bit duration, an ETU (Elementary Time
Unit), is equal to 9.44µs (1/106kHz).
These characters, framed by a Start Of Frame
(SOF) and an End Of Frame (EOF), are put to-
Figure 5. SRI4K Request Frame Character Format
Table 2. Bit Description
b
1
Bit
b
b
to b
0
9
8
10% ASK MODULATION
OF THE 13.56MHz WAVE,
GENERATED BY THE READER
DATA BIT TO TRANSMIT
TO THE
0
) transmitted first, as shown in
1 ETU
SRI4K
Stop bit used to indicate the end of a character
Start bit used to synchronize the transmission
Information Byte (command, address or data)
Start
"0"
b0
LSb
b1
b2
Description
b3
Information Byte
Figure
b4
Transfer time for one data bit is 1/106 kHz
b5
by the ASK demodulator. For the SRI4K to decode
correctly the information it receives, the reader
must 10% amplitude-modulate the 13.56MHz
wave before sending it to the SRI4K. This is repre-
sented in
106 kbits/s.
gether to form a Command Frame as shown in
Figure
addresses, data, a CRC and an EOF as defined in
the ISO14443-3 type B Standard. If an error is de-
tected during data transfer, the SRI4K does not
execute the command, but it does not generate an
error frame.
b6
11.. A frame includes an SOF, commands,
b7
Figure
The information byte is sent with the least
MSb
b8
4.. The data transfer rate is
Stop
"1"
b9
significant bit first
Value
b
b
0
9
= 0
= 1
AI10880
ai07664
SRI4K
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