mfrc531 NXP Semiconductors, mfrc531 Datasheet - Page 101

• Manufacturer Part Number: mfrc531
• Description: Iso/iec 14443 Reader Ic
• Manufacturer: NXP Semiconductors

NXP Semiconductors
MFRC531_34
Product data sheet
PUBLIC
15.2.1.1 TX control
15.2.1 Measurements using the serial signal switch
15.2 Test signals
The MFRC531 allows different kinds of signal measurements. These measurements can
be used to check the internally generated and received signals using the serial signal
switch as described in
In addition, the MFRC531 enables users to select between:
These measurements can be helpful during the design-in phase to optimize the receiver’s
behavior or for test purposes.
Using the serial signal switch on pin MFOUT, data is observed that is sent to the card or
received from the card.
Table 164. Signal routed to pin MFOUT
Remark: The routing of the Manchester or the Manchester with subcarrier signal to pin
MFOUT is only possible at 106 kBd based on ISO/IEC 14443 A.
Figure 25
The signal is measured on pin MFOUT using the serial signal switch to control the data
sent to the card. Setting the flag MFOUTSelect[2:0] = 010 sends the data to the card
coded as NRZ. Setting MFOUTSelect[2:0] = 001 shows the data as a Miller coded signal.
The RFOut signal is measured directly on the antenna and gives the RF signal pulse
shape. Refer to Application note Directly matched Antenna - Excel calculation
detail information on the RF signal pulse.
SignalToMFOUT
0
0
0
0
0
0
0
0
1
•
•
internal analog signals for measurement on pin AUX
internal digital signals for observation on pin MFOUT (based on register selections)
shows as an example of an ISO/IEC 14443 A communication.
Rev. 3.4 — 26 January 2010
MFOUTSelect[2:0]
000
001
010
011
100
101
110
111
X
Section 9.11 on page
Table 164
056634
gives an overview of the different signals available.
Signal routed to pin MFOUT
LOW
HIGH
envelope
transmit NRZ
Manchester with subcarrier
Manchester
reserved
reserved
digital test signal
35.
ISO/IEC 14443 reader IC
MFRC531
© NXP B.V. 2010. All rights reserved.
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