PXN20RM Datasheet, PDF (1081/1376 Pages) Freescale Semiconductor, Inc – PXN20 Microcontroller

Chapter 34
Analog-to-Digital Converter (ADC)
34.1 Introduction
The ADC module contains advanced features for normal, injected, and triggered injected conversion,
along with offset cancellation and offset refresh control, and supports the interface to the Cross Triggering
Unit (CTU). The ADC contains user-configurable sampling and conversion times with a clock prescaler
unit to generate the ADC clock from the clock provided to the ADC digital interface. The ADC contains
“analog watchdogs” for comparing values of the converted data against user programmed thresholds and
interrupt generation based on threshold violation by the converted data.
NOTE
The CTU is not implemented on the PXN20.
34.1.1 Block Diagram
Figure 34-1 shows the ADC block diagram.
It can be configured to generate sampling signals for as many as 96 multiplexed analog input channels.
There are three types of input channels: internal channels (group 0 and 1), and external channels (group 2).
Interrupt lines
BUS
ADC Digital Interface
ADC Analog
Cross
Triggering
Unit
Figure 34-1. ADC Block Diagram
Freescale Semiconductor
PXN20 Microcontroller Reference Manual, Rev. 1
34-1