Datasheet
4.5.2.5 External Watchdog Monitor (EWM)
• Independent 1 kHz LPO clock source
• Output signal to gate an external circuit which is controlled by CPU service or external input
4.5.2.6 System Clocks
• Frequency-locked loop (FLL)
• Digitally-controlled oscillator (DCO)
• DCO frequency range is programmable
• Option to program DCO frequency for a 32,768 Hz external reference clock source
• Internal or external reference clock can be used to control the FLL
• 0.2% resolution using 32 kHz internal reference clock
• Phase-locked loop (PLL)
• Voltage-controlled oscillator (VCO)
• External reference clock is used to control the PLL
• Modulo VCO frequency divider Phase/Frequency detector
• Integrated loop filter
• Internal reference clock generator
• Slow clock with nine trim bits for accuracy
• Fast clock with four trim bits
• Can be used to control the FLL
• Either the slow or the fast clock can be selected as the clock source for the MCU
• Can be used as a clock source for other on-chip peripherals
• External clock from the Crystal Oscillator (XOSC)
• Can be used to control the FLL and/or the PLL
• Can be selected as the clock source for the MCU
• External clock monitor with reset request capability
• Lock detector with interrupt request capability for use with the PLL
• Auto Trim Machine (ATM) for trimming both the slow and fast internal reference clocks
• Multiple clock source options available for most peripherals
Memories and Memory Interfaces
4.5.3.1 On-Chip Memory
• 50MHz performance devices
• Up to 512KB program flash memory
• Flexmemory block contains up to 64KB FlexNVM and 4KB FlexRAM with up to 4KB EEPROM capability
• Up to 64KB SRAM
• 72MHz performance devices
• Up to 256KB program flash memory
• Flexmemory block contains up to 32KB FlexNVM and 2KB FlexRAM with up to 2KB EEPROM capability
• Up to 64KB SRAM
• 100MHz performance devices
• Up to 512KB program flash memory
• Flexmemory block contains up to 256KB FlexNVM and 4KB FlexRAM with up to 4KB EEPROM capability
• Up to 128KB SRAM
• 120MHz performance devices
• Up to 1024KB program flash memory
4.5.3
Memories and Memory Interfaces
K20 Family Product Brief, Rev. 11, 08/2012
Freescale Semiconductor, Inc. 37