27.3 External Crystal Connections
The connections with a crystal is shown in the following figure. External load capacitors
and feedback resistor are not required.
RTC Oscillator Module
EXTAL32
Crystal or Resonator
XTAL32
V
SS
Figure 27-2. Crystal Connections
27.4 Memory Map/Register Descriptions
RTC oscillator control bits are part of the RTC registers. Refer to RTC Control register
for more details.
27.5 Functional Description
, the module includes an amplifier which supplies the negative
resistor for the RTC oscillator. The gain of the amplifier is controlled by the amplitude
detector, which optimizes the power consumption. A schmitt trigger is used to translate
the sine-wave generated by this oscillator to a pulse clock out, which is a reference clock
for the RTC digital core.
The oscillator includes an internal feedback resistor of approximately 100 M
Ω
between
EXTAL32 and XTAL32.
In addition, there are two programmable capacitors with this oscillator, which can be
used as the Cload of the oscillator. The programmable range is from 0pF to 30pF.
Chapter 27 RTC Oscillator (OSC32K)
K22F Sub-Family Reference Manual , Rev. 3, 7/2014
Freescale Semiconductor, Inc.
583
Содержание MK22FN256VDC12
Страница 2: ...K22F Sub Family Reference Manual Rev 3 7 2014 2 Freescale Semiconductor Inc...
Страница 136: ...Human machine interfaces K22F Sub Family Reference Manual Rev 3 7 2014 136 Freescale Semiconductor Inc...
Страница 164: ...Module clocks K22F Sub Family Reference Manual Rev 3 7 2014 164 Freescale Semiconductor Inc...
Страница 246: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 246 Freescale Semiconductor Inc...
Страница 328: ...Kinetis Flashloader Status Error Codes K22F Sub Family Reference Manual Rev 3 7 2014 328 Freescale Semiconductor Inc...
Страница 360: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 360 Freescale Semiconductor Inc...
Страница 388: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 388 Freescale Semiconductor Inc...
Страница 402: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 402 Freescale Semiconductor Inc...
Страница 500: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 500 Freescale Semiconductor Inc...
Страница 670: ...Flash memory map for EzPort access K22F Sub Family Reference Manual Rev 3 7 2014 670 Freescale Semiconductor Inc...
Страница 680: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 680 Freescale Semiconductor Inc...
Страница 744: ...Application information K22F Sub Family Reference Manual Rev 3 7 2014 744 Freescale Semiconductor Inc...
Страница 784: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 784 Freescale Semiconductor Inc...
Страница 794: ...Initialization Application Information K22F Sub Family Reference Manual Rev 3 7 2014 794 Freescale Semiconductor Inc...
Страница 960: ...Example configuration for chained timers K22F Sub Family Reference Manual Rev 3 7 2014 960 Freescale Semiconductor Inc...
Страница 1036: ...Device mode IRC48 operation K22F Sub Family Reference Manual Rev 3 7 2014 1036 Freescale Semiconductor Inc...
Страница 1040: ...USB Voltage Regulator Module Signal Descriptions K22F Sub Family Reference Manual Rev 3 7 2014 1040 Freescale Semiconductor Inc...
Страница 1094: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 1094 Freescale Semiconductor Inc...
Страница 1128: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 1128 Freescale Semiconductor Inc...
Страница 1216: ...Application information K22F Sub Family Reference Manual Rev 3 7 2014 1216 Freescale Semiconductor Inc...
Страница 1298: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 1298 Freescale Semiconductor Inc...
Страница 1312: ...K22F Sub Family Reference Manual Rev 3 7 2014 1312 Freescale Semiconductor Inc...