ZHCSHW1C March 2018 – January 2019 ADS1260 , ADS1261
PRODUCTION DATA.
The ADC integrates a level-shift voltage that can be connected to the AINCOM pin by an internal switch. As shown in Figure 56, the level-shift voltage is the mid-voltage between AVDD and AVSS. The purpose of the voltage is to shift the signal level of floating sensors to within the input range of the ADC. Isolated thermocouples and piezoelectric sensors are examples of sensors that are suitable for connection to the level-shift voltage. For these sensors, connect the negative lead to the AINCOM pin and enable the level-shift voltage.
The turn-on time of the level-shift voltage depends on the total external capacitance connected from the AINCOM pin to ground or AVSS. Table 5 lists the level-shift voltage settling times for various load capacitance. Be certain the level-shift voltage is fully settled before starting a conversion.
LOAD CAPACITANCE | LEVEL-SHIFT VOLTAGE SETTLING TIME |
---|---|
0.1 µF | 0.22 ms |
1 µF | 2.2 ms |
10 µF | 22 ms |