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.
To minimize EMI, use a low-inductance path for the digital output traces, and consider using a series termination resistor (e.g., 22-33 ohms) at the output of the device. Additionally, use a shielded cable or a twisted pair for the digital output signals, and keep the digital output signals away from the analog input signals.
The recommended power-up sequence is to apply the analog power supply (AVDD) first, followed by the digital power supply (DVDD), and then the clock signal. This sequence helps to ensure that the device powers up correctly and minimizes the risk of latch-up or other power-up related issues.
The ADS7881IPFBR has an internal calibration circuit that can be used to calibrate the device. The calibration process involves applying a known input voltage to the device and then reading the output code. The calibration data can then be used to correct for any offset or gain errors in the device. Texas Instruments provides a calibration procedure in the device's datasheet and application notes.
The maximum clock frequency that can be used with the ADS7881IPFBR is 20 MHz. However, the actual clock frequency that can be used may be limited by the specific application and the device's operating conditions. It is recommended to consult the device's datasheet and application notes for more information on clock frequency limitations.
ADS7881IPFBR datasheet
by Texas Instruments
Findchips
