LM3S1969 Datasheet, PDF (394/677 Pages) Texas Instruments – Stellaris® LM3S1969 Microcontroller

OBSOLETE: TI has discontinued production of this device.
Analog-to-Digital Converter (ADC)
Figure 11-4. Differential Sampling Range, V_{IN_ODD} = 2.25 V
ADC Conversion Result
0x3FF
0x2FF
0x1FF
0.75 V
-1.5 V
2.25 V
3.0 V
0.75 V
- Input Saturation
1.5 V
VIN_EVEN
DV
11.3.6
11.3.7
Test Modes
There is a user-available test mode that allows for loopback operation within the digital portion of
the ADC module. This can be useful for debugging software without having to provide actual analog
stimulus. This mode is available through the ADC Test Mode Loopback (ADCTMLB) register (see
page 424).
Internal Temperature Sensor
The temperature sensor serves two primary purposes: 1) to notify the system that internal temperature
is too high or low for reliable operation, and 2) to provide temperature measurements for calibration
of the Hibernate module RTC trim value.
The temperature sensor does not have a separate enable, since it also contains the bandgap
reference and must always be enabled. The reference is supplied to other analog modules; not just
the ADC.
The internal temperature sensor provides an analog temperature reading as well as a reference
voltage. The voltage at the output terminal SENSO is given by the following equation:
SENSO = 2.7 - ((T + 55) / 75)
This relation is shown in Figure 11-5 on page 395.
394
July 24, 2012
Texas Instruments-Production Data