Datasheet

Appendix A Electrical Characteristics
MC9S08QG8 and MC9S08QG4 Data Sheet, Rev. 5
274 Freescale Semiconductor
A.7 External Oscillator (XOSC) and Internal Clock Source (ICS)
Characteristics
Reference Figure A-7 for crystal or resonator circuit.
Table A-8. XOSC and ICS Specifications (Temperature Range = –40 to 125°C Ambient)
Characteristic Symbol Min Typ Max Unit
Internal reference frequency — factory trimmed at V
DD
= 3.6V and
temperature = 25°C
f
int_ft
— 31.25 — kHz
Oscillator crystal or resonator (EREFS = 1, ERCLKEN = 1)
Low range (RANGE = 0)
High range (RANGE = 1) FEE or FBE mode
1
High range (RANGE = 1), high gain (HGO = 1), FBELP mode
High range (RANGE = 1), low power (HGO = 0), FBELP mode
f
lo
f
hi
f
hi
f
hi
32
1
1
1
—
—
—
—
38.4
5
16
8
kHz
MHz
MHz
MHz
Load capacitors
C
1
C
2
See Note
2
Feedback resistor
Low range (32 kHz to 38.4 kHz)
High range (1 MHz to 16 MHz)
R
F
10
1
MΩ
MΩ
Series resistor — Low range
Low Gain (HGO = 0)
High Gain (HGO = 1)
R
S
—
—
0
100
—
—
kΩ
Series resistor — High range
Low Gain (HGO = 0)
High Gain (HGO = 1)
≥ 8 MHz
4 MHz
1 MHz
R
S
—
—
—
0
0
0
0
10
20
kΩ
Crystal start-up time
3, 4
Low range, low power
Low range, high power
High range, low power
High range, high power
t
CSTL
t
CSTH
—
—
—
—
200
400
5
15
—
—
—
—
ms
Internal reference start-up time
t
IRST
—60100μs
Square wave input clock frequency (EREFS = 0, ERCLKEN = 1)
FEE or FBE mode
2
FBELP mode
f
extal
0.03125
0
—
—
5
20
MHz
MHz
Internal reference frequency - untrimmed
5
f
int_ut
25 32.7 41.66 kHz
Internal reference frequency - trimmed
f
int_t
31.25 — 39.06 kHz
DCO output frequency range - untrimmed
5
f
dco
= 512 * f
int_ut
f
dco_ut
12.8 16.8 21.33 MHz
DCO output frequency range - trimmed
f
dco_t
16 — 20 MHz