MC68HC908LJ12CPB FREESCALE [Freescale Semiconductor, Inc], MC68HC908LJ12CPB Datasheet - Page 306

• Manufacturer Part Number: MC68HC908LJ12CPB
• Description: 8-bit microcontroller units
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

15.4.6 Monotonicity
MC68HC908LJ12
Freescale Semiconductor
NOTE:
—
Rev. 2.1
Finally, 8-bit truncation mode will place the eight MSBs in ADC data
register low (ADRL). The two LSBs are dropped. This mode of operation
is used when compatibility with 8-bit ADC designs are required. No
interlocking between ADRH and ADRL is present.
Quantization error is affected when only the most significant eight bits
are used as a result. See
The conversion process is monotonic and has no missing codes.
RESULT
003
002
001
000
8-BIT
RESULT
10-BIT
00B
00A
009
008
007
006
005
004
003
002
001
000
Analog-to-Digital Converter (ADC)
Figure 15-3. 8-Bit Truncation Mode Error
1/2
IDEAL 10-BIT CHARACTERISTIC
WITH QUANTIZATION = ±1/2
1 1/2
IDEAL 8-BIT CHARACTERISTIC
WITH QUANTIZATION = ±1/2
1/2
2 1/2
3 1/2
Figure
4 1/2
5 1/2
1 1/2
15-3.
6 1/2
7 1/2
8 1/2
Analog-to-Digital Converter (ADC)
9 1/2
WHEN TRUNCATION IS USED,
ERROR FROM IDEAL 8-BIT = 3/8 LSB
DUE TO NON-IDEAL QUANTIZATION.
2 1/2
INPUT VOLTAGE
REPRESENTED AS 10-BIT
INPUT VOLTAGE
REPRESENTED AS 8-BIT
10-BIT TRUNCATED
TO 8-BIT RESULT
Technical Data
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