MC9RS08LE4 Datasheet, PDF (16/30 Pages) Freescale Semiconductor, Inc – MCU Block Diagram

External Oscillator (XOSC) Characteristics
3.8 External Oscillator (XOSC) Characteristics
Refer to Figure 12 for crystal or resonator circuit.
Table 9. External Oscillator Specifications (Temperature Range = –40 to 85°C Ambient)
Num C
Characteristic
Symbol
Min Typical¹ Max
Oscillator crystal or resonator (EREFS = 1)
Low range, ( IREFS = x)
1
D
High range, FLL bypassed external
(CLKS = 10, IREFS = x)
High range, FLL engaged external
(CLKS = 00, IREFS = 0)
f_lo
32
f_{hi_byp}
1
f_{hi_eng}
1
—
38.4
—
5
—
5
2
D
Load capacitors
C₁
C₂
See Note ²
Feedback resistor
3
D
Low range (32 kHz to 100 kHz)
R_F
10
High range (1 MHz to 16 MHz)
1
Series resistor
Low range
Low Gain (HGO = 0)
—
0
—
High Gain (HGO = 1)
—
100
—
4
D
High range
Low Gain (HGO = 0)
R_S
—
0
—
High Gain (HGO = 1)
≥ 8 MHz
—
0
—
4 MHz
—
10
—
1 MHz
—
20
—
Crystal start-up time ^{3, 4}
5
D
Low range
High range
t
CSTL
—
500
—
t
CSTH
—
4
—
1 _{Data in Typical column was characterized at 3.0 V, 25 °C or is typical recommended value.}
2 _{See crystal or resonator manufacturer’s recommendation.}
3 _{This parameter is characterized and not tested on each device.}
4 _{Proper PC board layout procedures must be followed to achieve specifications.}
Unit
kHz
MHz
MHz
MΩ
kΩ
ms
EXTAL
XOSC
R_F
XTAL
R_S
Crystal or Resonator
C₁
C₂
Figure 12. Typical Crystal or Resonator Circuit
MC9RS08LE4 MCU Data Sheet, Rev. 2
16
Freescale Semiconductor