NXP Semiconductors
AN11744
PN5180 Evaluation board quick start guide
AN11744 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2018. All rights reserved.
Application note Rev. 1.3 — 2 February 2018
COMPANY PUBLIC 371213 25 / 45
settings depend on each other, so it is almost impossible to derive a deterministic
adjustment. On the other enabling the test bus slightly changes the Rx performance, so
the behavior with enabled or disabled test but can be different.
Therefore, it is recommended to use a Matrix test, which simply tests all relevant
combination of register settings. The result matrix shows easily the optimum settings.
This Matrix test is provided in the NFC cockpit.
4.7.1 Rx parameters
Typically, 3 or 4 (or even more) receiver settings need to be optimized for each protocol
and antenna design:
• RxGain: 0 ... 3
• HPCF: 0 ... 3
• MinLevel: 0 ... 15
• MinLevelP: 0 ... 15 (only BPSK)
Even though the default values (as delivered with the PNEV5180B) can be taken as
reference and starting point, the optimum might be different from the default. Changing
one parameter might require another parameter to change, too. At the end even several
“optima” might occur, which show similar performance.
There might be external influence like noise (e.g. from an LCD or other electronic
circuitry) resulting in a different optimum.
So, it is very difficult to define a clear and deterministic approach to optimize these Rx
settings, especially without knowing the external influence. However, for a high-end
reader design these settings play a significant role for a good performance.
An easy solution is the Rx Matrix Test. This tool simply tries each combination of
settings, and reports the number of proper receptions.
4.7.2 Rx Matrix test principle
The Rx matrix controls the PNEV5180B evaluation board and allows to configure:
• Free number of trials (per register combination)
• Free number and combination of register bits
• Free limit of minimum and maximum value
• Free choice of “protocol” (RF Configuration)
• Optional voltage level control of the LMA, using a Keysight AWG
The tool supports the digital and analog test signals, if needed. Especially the digital test
signal might be helpful to trigger a LMA test setup.
The Fig 23 shows the basic test setup, using a reference card, placed on the PCD
antenna in a certain distance. The reference card might a typical type A or B card (or any
other card that is supported by the PN5180).
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