Texas Instruments recommends a 4-layer PCB with a solid ground plane, and to keep the analog and digital signals separate. The analog input traces should be short and direct, and the digital output traces should be routed away from the analog inputs. Additionally, decoupling capacitors should be placed close to the device's power pins.
The ADS7822U/2K5G4 has a built-in POR circuit that resets the device when the power supply voltage rises above 1.5V. To ensure proper operation, the power supply voltage should be ramped up slowly (less than 10ms) and the digital interface should not be accessed until the power supply voltage has reached its nominal value.
The maximum sampling rate of the ADS7822U/2K5G4 is 200ksps. However, the device's power consumption increases with the sampling rate. At 200ksps, the device consumes around 1.5mA, while at 10ksps, it consumes around 0.5mA.
The ADS7822U/2K5G4 has an internal calibration circuit that can be used to calibrate the device. The recommended calibration procedure involves applying a known input voltage and reading the output code, then adjusting the internal calibration registers to achieve the desired accuracy. Texas Instruments provides a calibration procedure in the device's datasheet and application notes.
The ADS7822U/2K5G4's accuracy and linearity are affected by temperature. The device's offset and gain errors increase with temperature, and the device's linearity decreases. To compensate for temperature effects, the device's internal temperature sensor can be used to monitor the temperature, and the output data can be corrected using temperature correction coefficients provided in the device's datasheet.
ADS7822U/2K5G4 datasheet
by Texas Instruments
