LM3S6938 Luminary Micro, Inc, LM3S6938 Datasheet - Page 460

• Manufacturer Part Number: LM3S6938
• Description: Lm3s6938 Arm Microcontroller
• Manufacturer: Luminary Micro, Inc

Analog Comparators
17.2.1
460
Table 17-3. Comparator 2 Operating Modes
Internal Reference Programming
The structure of the internal reference is shown in Figure 17-3 on page 460. This is controlled by a
single configuration register (ACREFCTL). Table 17-4 on page 460 shows the programming options
to develop specific internal reference values, to compare an external voltage against a particular
voltage generated internally.
Figure 17-3. Comparator Internal Reference Structure
VREF
Table 17-4. 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+
reserved
RNG=X
C2+
C0+
Vref
8R
Output
n/a
n/a
n/a
n/a
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
Interrupt
R
yes
yes
yes
yes
14
Preliminary
ADCTrigger
Decoder
yes
yes
yes
yes
R
1
R
0
8R
internal
reference
July 25, 2008