s908qc16g0cdte Freescale Semiconductor, Inc, s908qc16g0cdte Datasheet - Page 31

• Manufacturer Part Number: s908qc16g0cdte
• Description: M68hc08 Family Of 8-bit Microcontroller Units Mcus
• Manufacturer: Freescale Semiconductor, Inc

Chapter 3
10-Bit Analog-to-Digital Converter (ADC10) Module
3.1 Introduction
This section describes the 10-bit successive approximation analog-to-digital converter (ADC10).
The ADC10 module shares its pins with general-purpose input/output (I/O) port pins. See
port location of these shared pins. The ADC10 on this MCU uses V
pins. This MCU uses BUSCLKX4 as its alternate clock source for the ADC. This MCU does not have a
hardware conversion trigger.
3.2 Features
Features of the ADC10 module include:
3.3 Functional Description
The ADC10 uses successive approximation to convert the input sample taken from ADVIN to a digital
representation. The approximation is taken and then rounded to the nearest 10- or 8-bit value to provide
greater accuracy and to provide a more robust mechanism for achieving the ideal code-transition voltage.
Figure 3-2
For proper conversion, the voltage on ADVIN must fall between V
or exceeds V
a 8-bit representation. If ADVIN is equal to or less than V
Input voltages between V
Freescale Semiconductor
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Linear successive approximation algorithm with 10-bit resolution
Output formatted in 10- or 8-bit right-justified format
Single or continuous conversion (automatic power-down in single conversion mode)
Configurable sample time and conversion speed (to save power)
Conversion complete flag and interrupt
Input clock selectable from up to three sources
Operation in wait and stop modes for lower noise operation
Selectable asynchronous hardware conversion trigger
shows a block diagram of the ADC10
REFH
, the converter circuit converts the signal to $3FF for a 10-bit representation or $FF for
Input voltage must not exceed the analog supply voltages.
REFH
and V
MC68HC08QY/QT Family Data Sheet, Rev. 2
REFL
are straight-line linear conversions.
NOTE
REFL
, the converter circuit converts it to $000.
DD
REFH
and V
and V
SS
REFL
as its supply and reference
. If ADVIN is equal to
Figure 3-1
for
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