Analog-to-Digital Converter (ADC)
Technical Data
MC68HC908GP32
•
MC68HC08GP32
—
Rev. 6
96
Analog-to-Digital Converter (ADC)
MOTOROLA
ADICLK — ADC Input Clock Select Bit
ADICLK selects either the bus clock or CGMXCLK as the input clock
source to generate the internal ADC clock. Reset selects CGMXCLK
as the ADC clock source.
If the external clock (CGMXCLK) is equal to or greater than 1 MHz,
CGMXCLK can be used as the clock source for the ADC. If
CGMXCLK is less than 1 MHz, use the PLL-generated bus clock as
the clock source. As long as the internal ADC clock is at
approximately 1 MHz, correct operation can be guaranteed.
1 = Internal bus clock
0 = External clock (CGMXCLK)
Table 5-2. ADC Clock Divide Ratio
ADIV2
ADIV1
ADIV0
ADC Clock Rate
0
0
0
ADC input clock
÷
1
0
0
1
ADC input clock
÷
2
0
1
0
ADC input clock
÷
4
0
1
1
ADC input clock
÷
8
1
X
X
ADC input clock
÷
16
X = don’t care
ADC input clock frequency
ADIV2 ADIV0
–
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1MHz
=
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Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
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