XC167CI_02 Datasheet, PDF (65/79 Pages) Infineon Technologies AG – 16-Bi t Single-Chip Microcontroller Preliminary

XC167
Derivatives
Preliminary
Timing Parameters
For a period of N × TCM the accumulated PLL jitter is defined by the corresponding
deviation D_N:
D_N [ns] = ±(1.5 + 6.32 × N / f_MC); f_MC in [MHz], N = number of consecutive TCMs.
So, for a period of 3 TCMs @ 20 MHz and K = 12: D₃ = ±(1.5 + 6.32 × 3 / 20) = 2.448 ns.
This formula is applicable for K × N < 95. For longer periods the K×N=95 value can be
used. This steady value can be approximated by: D_Nmax [ns] = ±(1.5 + 600 / (K × f_MC)).
Acc. jitter D_N
ns
±8
K=15 K=12 K=10 K=8
±7
±6
±5
±4
±3
2400MMHzHz
±2
±1
K=6
K=5
01
5
10
15
20
25
N
mcb04413_xc.vsd
Figure 15 Approximated Accumulated PLL Jitter
Note: The bold lines indicate the minimum accumulated jitter which can be achieved by
selecting the maximum possible output prescaler factor K.
Different frequency bands can be selected for the VCO, so the operation of the PLL can
be adjusted to a wide range of input and output frequencies:
Table 15 VCO Bands for PLL Operation
PLLCON.PLLVB VCO Frequency Range
Base Frequency Range
00
100 … 150 MHz
20 … 80 MHz
01
150 … 200 MHz
40 … 130 MHz
10
200 … 250 MHz
60 … 180 MHz
11
Reserved
Data Sheet
61
V1.0, 2002-10