Analog Power; Ddad ); Analog Ground; Ssad ) - ROHS MC9S08QE128 Reference Manual

10.2.1 Analog Power (V
The ADC analog portion uses V
internally to V . If externally available, connect the V
DD
External filtering may be necessary to ensure clean V
10.2.2 Analog Ground (V
The ADC analog portion uses V
internally to V . If externally available, connect the V
SS
10.2.3 Voltage Reference High (V
V is the high reference voltage for the converter. In some packages, V
REFH
V . If externally available, V
DDAD
driven by an external source that is between the minimum V
must never exceed V
DDAD
10.2.4 Voltage Reference Low (V
V is the low reference voltage for the converter. In some packages, V
REFL
V . If externally available, connect the V
SSAD
10.2.5

Analog Channel Inputs (ADx)

The ADC module supports up to 28 separate analog inputs. An input is selected for conversion through the
ADCH channel select bits.
10.3 Register Definition
These memory mapped registers control and monitor operation of the ADC:
• Status and control register, ADCSC1
• Status and control register, ADCSC2
• Data result registers, ADCRH and ADCRL
• Compare value registers, ADCCVH and ADCCVL
• Configuration register, ADCCFG
• Pin enable registers, APCTL1, APCTL2, APCTL3
10.3.1

Status and Control Register 1 (ADCSC1)

This section describes the function of the ADC status and control register (ADCSC1). Writing ADCSC1
aborts the current conversion and initiates a new conversion (if the ADCH bits are equal to a value other
than all 1s).
Freescale Semiconductor
)
DDAD
as its power connection. In some packages, V
DDAD
)
SSAD
as its ground connection. In some packages, V
SSAD
REFH
may be connected to the same potential as V
REFH
).
REFL
REFL
MC9S08QE128 MCU Series Reference Manual, Rev. 2
12-bit Analog-to-Digital Converter (S08ADCV1)
pin to the same voltage potential as V
DDAD
for good results.
DDAD
pin to the same voltage potential as V
SSAD
)
spec and the V
DDAD
)
pin to the same voltage potential as V
is connected
DDAD
is connected
SSAD
is connected internally to
REFH
, or may be
DDAD
potential (V
DDAD
is connected internally to
REFL
.
SSAD
.
DD
.
SS
REFH
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