K20P81M72SF1 Datasheet, PDF (29/74 Pages) Freescale Semiconductor, Inc – K20 Sub-Family

Peripheral operating requirements and behaviors
Table 14. Oscillator DC electrical specifications (continued)
Symbol
R_F
R_S
Description
Feedback resistor — low-frequency, low-power
mode (HGO=0)
Feedback resistor — low-frequency, high-gain
mode (HGO=1)
Feedback resistor — high-frequency, low-power
mode (HGO=0)
Feedback resistor — high-frequency, high-gain
mode (HGO=1)
Series resistor — low-frequency, low-power
mode (HGO=0)
Series resistor — low-frequency, high-gain mode
(HGO=1)
Series resistor — high-frequency, low-power
mode (HGO=0)
Series resistor — high-frequency, high-gain
mode (HGO=1)
Min.
—
—
—
—
—
—
—
Typ.
—
10
—
1
—
200
—
Max.
—
—
—
—
—
—
—
Unit
Notes
MΩ
2, 4
MΩ
MΩ
MΩ
kΩ
kΩ
kΩ
—
0
—
kΩ
V_pp5 ^{Peak-to-peak amplitude of oscillation (oscillator}
—
0.6
—
V
mode) — low-frequency, low-power mode
(HGO=0)
Peak-to-peak amplitude of oscillation (oscillator
—
V_DD
—
V
mode) — low-frequency, high-gain mode
(HGO=1)
Peak-to-peak amplitude of oscillation (oscillator
—
0.6
—
V
mode) — high-frequency, low-power mode
(HGO=0)
Peak-to-peak amplitude of oscillation (oscillator
—
V_DD
—
V
mode) — high-frequency, high-gain mode
(HGO=1)
1. V_DD=3.3 V, Temperature =25 °C
2. See crystal or resonator manufacturer's recommendation
3. C_x,C_y can be provided by using either the integrated capacitors or by using external components.
4. When low power mode is selected, R_F is integrated and must not be attached externally.
5. The EXTAL and XTAL pins should only be connected to required oscillator components and must not be connected to any
other devices.
6.3.2.2 Oscillator frequency specifications
Table 15. Oscillator frequency specifications
Symbol
f_{osc_lo}
Description
Oscillator crystal or resonator frequency — low
frequency mode (MCG_C2[RANGE]=00)
Min.
32
Typ.
—
Max.
40
Table continues on the next page...
Unit
Notes
kHz
K20 Sub-Family Data Sheet, Rev. 2, 4/2012.
Freescale Semiconductor, Inc.
29