- Do partition the analog, digital, and power supply circuitry into separate sections on the PCB.
- Do use a single ground plane for analog and digital grounds.
- Do place the analog components close to the ADC pins using short, direct connections.
- Do keep the SCLK pin free of glitches and noise.
- Do verify that the analog input voltages are within the specified PGA input voltage range under all input conditions.
- Do tie unused analog input pins to midsupply to minimize input leakage current.
- Do provide current limiting to the analog inputs in case overvoltage faults occur.
- Do use an LDO regulator to reduce ripple voltage generated by switch-mode power supplies.
- Don't route digital clock traces in the vicinity of the CAPP and CAPN pins.
- Don't cross digital signals over analog signals.
- Don't allow the analog and digital power supply voltages to exceed 7 V under all conditions, including during power-up and power-down.
Figure 10-15 shows Do's and Don'ts of ADC circuit connections.
Figure 10-15 Dos and Don'ts Circuit Connections