The receive margin can therefore be expressed as follows.
Receive margin in smart card mode:
M =
|
0.5 –
– (L – 0.5) F –
(1 + F)
| ×
100%
M: Receive margin (%)
N: Ratio of clock frequency to bit rate (N = 372)
D: Clock duty cycle (D = 0 to 1.0)
L:
Frame length (L = 10)
F:
Absolute deviation of clock frequency
From this equation, if F = 0 and D = 0.5 the receive margin is as follows.
D = 0.5, F = 0
M = {0.5 – 1/(2
×
372)}
×
100%
= 49.866%
1
2N
|
D – 0.5
|
N
520
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