Datasheet

Electrical Specifications
Technical Data MC68HC908LJ12 — Rev. 2.1
398 Electrical Specifications Freescale Semiconductor
23.10 5.0V Oscillator Characteristics
23.11 3.3V Oscillator Characteristics
Table 23-8. 5.0V Oscillator Specifications
Characteristic Symbol Min Typ Max Unit
Internal oscillator clock frequency
f
ICLK
46k
47k
(1)
Notes:
1. Typical value reflect average measurements at midpoint of voltage range, 25 °C only.
48k Hz
External reference clock to OSC1
(2)
2. No more than 10% duty cycle deviation from 50%.
f
OSC
dc — 20M Hz
Crystal reference frequency
(3)
3. Fundamental mode crystals only.
f
XCLK
32.768k 4.9152M Hz
Crystal load capacitance
(4)
4. Consult crystal manufacturer’s data.
C
L
———
Crystal fixed capacitance
C
1
—
2 × C
L
(25p)
—F
Crystal tuning capacitance
C
2
—
2 × C
L
(25p)
—F
Feedback bias resistor
R
B
—10M—Ω
Series resistor
(5)
5. Not Required for high frequency crystals.
R
S
—100k—Ω
Table 23-9. 3.3V Oscillator Specifications
Characteristic Symbol Min Typ Max Unit
Internal oscillator clock frequency
f
ICLK
42.8k
43.4k
(1)
Notes:
1. Typical value reflect average measurements at midpoint of voltage range, 25 °C only.
44k Hz
External reference clock to OSC1
(2)
2. No more than 10% duty cycle deviation from 50%.
f
OSC
dc — 16M Hz
Crystal reference frequency
(3)
3. Fundamental mode crystals only.
f
XCLK
32.768k 4.9152M Hz
Crystal load capacitance
(4)
4. Consult crystal manufacturer’s data.
C
L
———
Crystal fixed capacitance
C
1
—
2 × C
L
(25p)
—F
Crystal tuning capacitance
C
2
—
2 ×
C
L
(25p)
—F
Feedback bias resistor
R
B
—10M—Ω
Series resistor
(5)
5. Not Required for high frequency crystals.
R
S
—100k—Ω