LM3S301 Luminary Micro, Inc, LM3S301 Datasheet - Page 299

• Manufacturer Part Number: LM3S301
• Description: Lm3s301 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

14.2.1
July 5, 2006
Table 14-2. Comparator 1 Operating Modes
a. C1o and C1+ signals share a single pin and may only be used as one or the other.
Internal Reference Programming
The structure of the internal reference is shown in Figure 14-3. This is controlled by a single
configuration register (ACREFCTL). Table 14-3 shows the programming options to develop
specific internal reference values, to compare an external voltage against a particular voltage
generated internally.
Figure 14-3. Comparator Internal Reference Structure
Table 14-3. Internal Reference Voltage and ACREFCTL Field Values
10
11
EN Bit Value
ACCNTL1
ASRCP
EN=0
ACREFCTL Register
VREF
RNG
EN
RNG Bit Value
RNG=X
VIN-
AVDD
C1-
C1-
8R
Preliminary
0 V (GND) for any value of VREF; however, it is recommended that
RNG=1 and VREF=0 for the least noisy ground reference.
reserved
R
VIN+
Vref
Output Reference Voltage Based on VREF Field Value
15
R
14
•••
Decoder
Comparator 1
•••
C1o/C1+
C1o/C1+
R
Output
1
R
0
8R
Interrupt
yes
yes
internal
reference
LM3S301 Data Sheet
ADCTrigger
yes
yes
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