Table b-11 oscillator characteristics, B.6.3, Phase locked loop – Motorola MC9S12GC-Family User Manual
Page 111: B.6.3 phase locked loop, Time t
Device User Guide — 9S12C128DGV1/D V01.05
111
time t
UPOSC
. The device features a clock monitor. A time-out is asserted if the frequency of the incoming
clock signal is below the Clock Monitor FailureAssert Frequency f
CMFA.
B.6.3 Phase Locked Loop
The oscillator provides the reference clock for the PLL. The PLL´s Voltage Controlled Oscillator (VCO)
is also the system clock source in self clock mode.
B.6.3.1 XFC Component Selection
This section describes the selection of the XFC components to achieve a good filter characteristics.
Table B-11 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)
f
OSC
0.5
16
MHz
1b
C
Crystal oscillator range (Pierce)
NOTES
:
1. Depending on the crystal a damping series resistor might be necessary
f
OSC
0.5
40
MHz
2
P
Startup Current
i
OSC
100
µ
A
3
C
Oscillator start-up time (Colpitts)
t
UPOSC
8
2
2. f
osc
= 4MHz, C = 22pF.
100
3
3. Maximum value is for extreme cases using high Q, low frequency crystals
ms
4
D
Clock Quality check time-out
t
CQOUT
0.45
2.5
s
5
P
Clock Monitor Failure Assert Frequency
f
CMFA
50
100
200
KHz
6
P
External square wave input frequency
4
4. XCLKS =0 during reset
f
EXT
0.5
50
MHz
7
D
External square wave pulse width low
t
EXTL
9.5
ns
8
D
External square wave pulse width high
t
EXTH
9.5
ns
9
D
External square wave rise time
t
EXTR
1
ns
10
D
External square wave fall time
t
EXTF
1
ns
11
D
Input Capacitance (EXTAL, XTAL pins)
C
IN
7
pF
12
C
DC Operating Bias in Colpitts Configuration
on EXTAL Pin
V
DCBIAS
1.1
V