Texas Instruments MSP430x4xx - Manual (Page 472)

Scan IF Operation
24-12 Scan IF
For each input there are two DAC registers to set the reference level as listed
in Table 24−3. Together with the last stored output of the comparator,
SIFxOUT, the two levels can be used as an analog hysteresis as shown in
Figure 24−6. The individual settings for the four inputs can be used to
compensate for mismatches between the sensors.
Table 24−3.Selected DAC Registers
Selected Output Bit,
SIFxOUT
Last Value of
SIFxOUT
DAC Register Used
SIF0OUT 0 SIFDACR0
1 SIFDACR1
SIF1OUT 0 SIFDACR2
1 SIFDACR3
SIF2OUT 0 SIFDACR4
1 SIFDACR5
SIF3OUT 0 SIFDACR6
1 SIFDACR7
Figure 24−6. Analog Hysteresis With DAC Registers
DAC Output Voltage
Input Voltage
SIF1OUT
Time
SIFDACR2
SIFDACR3
When TESTDX = 1, the SIFDACR6 and SIFDACR7 registers are used as the
comparator reference as described in Table 24−4.
Table 24−4.DAC Register Select When TESTDX = 1
SIFTESTS1(tsm) DAC Register Used
0 SIFDACR6
1 SIFDACR7