Device User Guide — 9S12DT128DGV2/D V02.15
121
Freescale Semiconductor
Clock Monitor Failure is asserted if the frequency of the incoming clock signal is below the Assert
Frequency fCMFA.
A.5.3 Phase Locked Loop
The oscillator provides the reference clock for the PLL. The PLLs Voltage Controlled Oscillator (VCO)
is also the system clock source in self clock mode.
A.5.3.1 XFC Component Selection
This section describes the selection of the XFC components to achieve a good filter characteristics.
Table A-15 Oscillator Characteristics
Conditions are shown in (Table A-4) unless otherwise noted
Num C
Rating
Symbol
Min
Typ
Max
Unit
1a
C Crystal oscillator range (Colpitts)
fOSC
0.5
16
MHz
1b
C Crystal oscillator range (Pierce) 1
NOTES:
1. Depending on the crystal a damping series resistor might be necessary
fOSC
0.5
40
MHz
2
P Startup Current
iOSC
100
A
3
C Oscillator start-up time (Colpitts)
tUPOSC
82
2. fosc = 4MHz, C = 22pF.
1003
3. Maximum value is for extreme cases using high Q, low frequency crystals
ms
4
D Clock Quality check time-out
tCQOUT
0.45
2.5
s
5
P Clock Monitor Failure Assert Frequency
fCMFA
50
100
200
KHz
6
P External square wave input frequency 4
4. XCLKS =0 during reset
fEXT
0.5
50
MHz
7
D External square wave pulse width low
tEXTL
9.5
ns
8
D External square wave pulse width high
tEXTH
9.5
ns
9
D External square wave rise time
tEXTR
1
ns
10
D External square wave fall time
tEXTF
1
ns
11
D Input Capacitance (EXTAL, XTAL pins)
CIN
7
pF
12
C
DC Operating Bias in Colpitts Conguration on
EXTAL Pin
VDCBIAS
1.1
V
13
P EXTAL Pin Input High Voltage4
VIH,EXTAL
0.75*VDDPLL
V
T EXTAL Pin Input High Voltage4
VIH,EXTAL
VDDPLL + 0.3
V
14
P EXTAL Pin Input Low Voltage4
VIL,EXTAL
0.25*VDDPLL
V
T EXTAL Pin Input Low Voltage4
VIL,EXTAL
VSSPLL - 0.3
V
15
C EXTAL Pin Input Hysteresis4
VHYS,EXTAL
250
mV