SRI4K-A3T/1GE STMicroelectronics, SRI4K-A3T/1GE Datasheet - Page 6

• 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

SRI4K
Request Start Of Frame. The SOF described in
Figure 6.
Figure 6. Request Start Of Frame
Request End Of Frame. The EOF shown in
ure 7.
Figure 7. Request End Of Frame
Output Data Transfer from the SRI4K to the
Reader (Answer Frame)
The data bits issued by the SRI4K use retro-mod-
ulation. Retro-modulation is obtained by modifying
the SRI4K current consumption at the antenna
(load modulation). The load modulation causes a
variation at the reader antenna by inductive cou-
Figure 8. Wave Transmitted using BPSK Sub-carrier Modulation
6/41
is composed of:
is composed of:
ETU
ETU
Data Bit to be Transmitted
847kHz BPSK Modulation
Generated by the SRI4K
0
0
b0
b0
to the Reader
0
b1
0
b1
0
0
b2
b2
Or
0
0
b3
b3
During a One-bit Data Transfer Time (1/106kHz)
0
0
b4
b4
Fig-
BPSK Modulation at 847kHz
0
0
b5
b5
–
–
–
–
–
–
–
pling. With appropriate detector circuitry, the read-
er is able to pick up information from the SRI4K.
To improve load-modulation detection, data is
transmitted using a BPSK encoded, 847kHz sub-
carrier frequency ƒ
specified in the ISO14443-2 type B Standard.
0
b6
0
b6
one falling edge,
followed by 10 ETUs at logic-0,
followed by a single rising edge,
followed by at least 2 ETUs (and at most 3) at
logic-1.
one falling edge,
followed by 10 ETUs at logic-0,
followed by a single rising edge.
0
0
b7
b7
0
b8
0
b8
s
as shown in
0
0
b9
b9
1
b10
Figure
b11
1
AI10881
8., and as
ai07665
ai07666