Absorb current spikes and noise with a simple technique

摘要

When using an 8- to 14-bit ADC in your system, it is critical that you understand the voltage-reference path to the converter. Figure 1 shows a circuit that accommodates the dynamics of the ADC's reference input. In this figure, the voltage-reference chip provides a voltage foundation for the conversion process and a capacitor, C_(L1), to absorb the ADC's internal reference circuitry current spikes and filter-reference noise (Reference 1). It is important not only to reduce voltage-reference noise in this circuit but also to balance the stability of the internal voltage-reference amplifier.