LM3S300 Luminary Micro, Inc, LM3S300 Datasheet - Page 331

• Manufacturer Part Number: LM3S300
• Description: Lm3s300 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

14.2.1
June 04, 2008
Table 14-3. Comparator 2 Operating Modes
a. C2o and C2+ 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 on page 331. This is controlled by a
single configuration register (ACREFCTL). Table 14-4 on page 331 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
VREF
Table 14-4. Internal Reference Voltage and ACREFCTL Field Values
ACCNTL2
ASRCP
00
01
10
11
ACREFCTL Register
EN Bit Value
RNG
EN
EN=0
Comparator 2
VIN-
C2-
C2-
C2-
C2-
AVDD
RNG Bit Value
VIN+
C2o/C2+
reserved
RNG=X
C0+
Vref
a
8R
Output
C2o/C2+
C2o/C2+
C2o/C2+
C2o/C2+
Output Reference Voltage Based on VREF Field Value
0 V (GND) for any value of VREF; however, it is recommended that RNG=1 and VREF=0
for the least noisy ground reference.
15
R
Interrupt
yes
yes
yes
yes
14
Preliminary
Decoder
R
1
R
0
8R
internal
reference
LM3S300 Microcontroller
331