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MC9S12KT256 Datasheet, PDF (580/594 Pages) Freescale Semiconductor, Inc – Microcontrollers | |||
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Deï¬ning the jitter as:
J(N)
=

max
ï£
1
â
t-N-m-----â
-a--t-nx----(o--N--m---)
,
1
â
N-t--m---â
--i-t-n-n---(-o-N---m--)-



NOTE
From the evaluation data a formula for tmax= f(N), resp. tmin = f(N) should
be derived.
Assuming no long term drift of the reference clock, the following will hold
lim J(N) = 0
Nââ
This is very important to notice with respect to timers, serial modules where a pre-scaler will eliminate the
effect of the jitter to a large extent.
Table A-20. PLL Characteristics
Conditions are shown in Table A-4 unless otherwise noted
Num C
Rating
Symbol
Min
Typ
Max
Unit
1 P Self Clock Mode frequency
fSCM
1
â
5.5
MHz
2 D VCO locking range
fVCO
8
â
50
MHz
3 D Lock Detector transition from Acquisition to Tracking
âtrk
3%
â
4%1
â
mode
4 D Lock Detection
âLock
0%
â
1.5%1
â
5 D Un-Lock Detection
âunl
0.5%
â
2.5%1
â
6 D Lock Detector transition from Tracking to Acquisition
âunt
6%
â
8%1
â
mode
7 C PLLON Total Stabilization delay2
8 D PLLON Acquisition mode stabilization delay2
9 D PLLON Tracking mode stabilization delay2
tstab
â
0.5
tacq
â
0.3
tal
â
0.2
â
ms
â
ms
â
ms
10 D Fitting parameter VCO loop gain
K1
â
â100
â
MHz/V
11 D Fitting parameter VCO loop frequency
f1
â
60
â
MHz
12 D Charge pump current acquisition mode
ich
â
â38.5
â
µA
13 D Charge pump current tracking mode
14 C Jitter ï¬t parameter 12
15 C Jitter ï¬t parameter 22
ich
â
âl3.5
â
µA
j1
â
â
1.1
%
j2
â
â
0.13
%
1 % deviation from target frequency
2 fOSC = 4MHz, fBUS = 25MHz equivalent fVCO = 50MHz: REFDV = #$03, SYNR = #$018, Cs = 4.7nF, Cp = 470pF, Rs = 10Kâ¦.
MC9S12KT256 Data Sheet, Rev 1.15
580
Freescale Semiconductor
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