10.2 Decoupling

Decoupling capacitors must be used at each supply pin to prevent supply or ground noise from degrading the dynamic performance of the ADC and to provide the ADC with a well of charge to minimize voltage ripple caused by current transients. The recommended supply decoupling scheme is to have a ceramic X7R 0201 0.1-μF and a X7R 0402 0.1-μF capacitor at each supply pin. The 0201 capacitor must be placed on the same layer as the device as close to the pin as possible to minimize the AC decoupling path length from the supply pin, through the capacitor, to the nearest adjacent ground pin. The 0402 capacitor should also be close to the pins. TI does not recommend placing all capacitors on the opposite board side. Each voltage supply should also have a single 10-μF decoupling capacitor near the device but the proximity to the supply pins is less critical.