
Analog-to-Digital Converter (ADC)
Technical Data
MC68HC908GR8A — Rev 0.0
84
Analog-to-Digital Converter (ADC)
MOTOROLA
5.7.1 ADC Analog Power Pin (VDDAD)/ADC Voltage Reference High Pin (VREFH)
The ADC analog portion uses VDDAD as its power pin. Connect the
VDDAD pin to the same voltage potential as VDD. External filtering may be
necessary to ensure clean VDDAD for good results.
NOTE:
For maximum noise immunity, route VDDAD carefully and place bypass
capacitors as close as possible to the package.
5.7.2 ADC Analog Ground Pin (VSSAD)/ADC Voltage Reference Low Pin (VREFL)
The ADC analog portion uses VSSAD as its ground pin. Connect the
VSSAD pin to the same voltage potential as VSS.
NOTE:
Route VSSAD cleanly to avoid any offset errors.
5.7.3 ADC Voltage In (VADIN)
VADIN is the input voltage signal from one of the six ADC channels to the
ADC module.