mc68hc908gr8b Freescale Semiconductor, Inc, mc68hc908gr8b Datasheet - Page 47

• Manufacturer Part Number: mc68hc908gr8b
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

3.3.2 Voltage Conversion
When the input voltage to the ADC equals V
input voltage equals V
straight-line linear conversion.
Freescale Semiconductor
INTERNAL DATA BUS
The ADC input voltage must always be greater than V
V
Connect the V
connect the V
V
AIEN
DDA
DDA
INTERRUPT
LOGIC
. V
pin should be routed carefully for maximum noise immunity.
COCO
READ DDRBx
WRITE DDRBx
WRITE PTBx
READ PTBx
REFL
REFH
CONVERSION
,
BUS CLOCK
COMPLETE
the ADC converts it to $00. Input voltages between V
RESET
CGMXCLK
must always be greater than or equal to V
SSA
DDA
pin to the same voltage potential as the V
pin to the same voltage potential as the V
ADIV2–ADIV0
MC68HC908GR8B Data Sheet, Rev. 3.0
Figure 3-2. ADC Block Diagram
ADC DATA REGISTER
GENERATOR
DDRBx
REFH
PTBx
CLOCK
ADC
ADC CLOCK
NOTE
NOTE
, the ADC converts the signal to $FF (full scale). If the
ADICLK
VOLTAGE IN
(V
ADC
ADIN
V
V
REFH
REFL
DISABLE
)
DISABLE
SSA
CHANNEL
REFL
SELECT
and less than
SS
ADC CHANNEL x
.
DD
PTBx
pin. The
pin, and
ADCH4–ADCH0
REFH
Functional Description
and V
REFL
are a
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