Texas Instruments recommends a 4-layer PCB with a solid ground plane, and to keep the analog and digital signals separate. The input signals should be routed close to the device, and the output signals should be routed away from the device. Additionally, decoupling capacitors should be placed close to the device's power pins.
The ADS820U does not require calibration, as it is a self-calibrating device. However, it is recommended to perform a system-level calibration to account for any errors introduced by the external circuitry. This can be done by applying a known input signal and adjusting the system's gain and offset to match the expected output.
The maximum sampling rate of the ADS820U is 100 kSPS. However, the actual sampling rate may be limited by the system's clock frequency, the input signal's bandwidth, and the device's settling time.
Yes, the ADS820U can be used in a multiplexed configuration. However, the device's input multiplexer should be controlled using an external signal, and the device's conversion time should be taken into account when designing the multiplexing scheme.
The ADS820U's digital output data is in a 16-bit, two's complement format. The data should be read from the device's output pins using a microcontroller or an FPGA, and then processed according to the system's requirements. The data can be converted to a more convenient format, such as a signed integer or a floating-point number, using software or hardware.
ADS820U datasheet
by Texas Instruments
