K40P81M100SF2_11 Datasheet, PDF (28/63 Pages) Freescale Semiconductor, Inc – Up to 100 MHz ARM Cortex-M4 core with DSP instructions delivering 1.25 Dhrystone MIPS per MHz

Peripheral operating requirements and behaviors
Table 15. Oscillator frequency specifications (continued)
Symbol
t_cst
Description
Crystal startup time — 32 kHz low-frequency,
low-power mode (HGO=0)
Crystal startup time — 32 kHz low-frequency,
high-gain mode (HGO=1)
Crystal startup time — 8 MHz high-frequency
(MCG_C2[RANGE]=01), low-power mode
(HGO=0)
Crystal startup time — 8 MHz high-frequency
(MCG_C2[RANGE]=01), high-gain mode
(HGO=1)
Min.
—
—
—
Typ.
TBD
800
4
Max.
—
—
—
Unit
Notes
ms
2, 3
ms
ms
—
3
—
ms
1. Other frequency limits may apply when external clock is being used as a reference for the FLL or PLL
2. Proper PC board layout procedures must be followed to achieve specifications.
3. Crystal startup time is defined as the time between the oscillator being enabled and the OSCINIT bit in the MCG_S register
being set.
6.3.3 32kHz Oscillator Electrical Characteristics
This section describes the module electrical characteristics.
6.3.3.1 32kHz oscillator DC electrical specifications
Table 16. 32kHz oscillator DC electrical specifications
Symbol
V_BAT
R_F
C_para
C_load
V_pp
Description
Supply voltage
Internal feedback resistor
Parasitical capacitance of EXTAL32 and XTAL32
Internal load capacitance (programmable)
Peak-to-peak amplitude of oscillation
Min.
1.71
—
—
—
—
Typ.
—
100
2.5
15
0.6
Max.
Unit
3.6
V
—
MΩ
—
pF
—
pF
—
V
6.3.3.2 32kHz oscillator frequency specifications
Table 17. 32kHz oscillator frequency specifications
Symbol
f_{osc_lo}
t_start
Description
Oscillator crystal
Crystal start-up time
Min.
Typ.
Max.
Unit
—
32
—
kHz
—
1000
—
ms
1. Proper PC board layout procedures must be followed to achieve specifications.
Notes
1
6.4 Memories and memory interfaces
K40 Sub-Family Data Sheet Data Sheet, Rev. 4, 3/2011.
28
Preliminary
Freescale Semiconductor, Inc.