Information

Table 2-5. Clock modules

Module Description

Multi-clock generator (MCG) The MCG provides several clock sources for the MCU that include:

• Phase-locked loop (PLL) — Voltage-controlled oscillator (VCO)

• Frequency-locked loop (FLL) — Digitally-controlled oscillator (DCO)

• Internal reference clocks — Can be used as a clock source for other on-chip

peripherals

System oscillator The system oscillator, in conjunction with an external crystal or resonator,

generates a reference clock for the MCU.

Real-time clock oscillator The RTC oscillator has an independent power supply and supports a 32 kHz

crystal oscillator to feed the RTC clock. Optionally, the RTC oscillator can replace

the system oscillator as the main oscillator source.

2.4.5 Security and Integrity modules

The following security and integrity modules are available on this device:

Table 2-6. Security and integrity modules

Module Description

Cyclic Redundancy Check (CRC) Hardware CRC generator circuit using 16/32-bit shift register. Error detection for

all single, double, odd, and most multi-bit errors, programmable initial seed value,

and optional feature to transpose input data and CRC result via transpose register.

2.4.6 Analog modules

The following analog modules are available on this device:

Table 2-7. Analog modules

Module Description

16-bit analog-to-digital converters (ADC) 16-bit successive-approximation ADC

Analog comparators Compares two analog input voltages across the full range of the supply voltage.

6-bit digital-to-analog converters (DAC) 64-tap resistor ladder network which provides a selectable voltage reference for

applications where voltage reference is needed.

Voltage reference (VREF) Supplies an accurate voltage output that is trimmable in 0.5 mV steps. The VREF

can be used in medical applications, such as glucose meters, to provide a

reference voltage to biosensors or as a reference to analog peripherals, such as

the ADC, DAC, or CMP.

Module Functional Categories

K20 Sub-Family Reference Manual, Rev. 2, Feb 2012

54 Freescale Semiconductor, Inc.