ADR366B - High frequency behavior and decoupling

Good morning,

I am using the ADR366B voltage reference to supply an ADC (AD7476, unique pin for VDD and VRef).


I have two questions:


1. What is the high frequency behavior of the ADR366B voltage reference? Do you have an idea of its output impedance and load regulation in the range [100 kHz;100 MHz]?

Indeed, I have noticed during testing that ADC conversion fail under 2.2 µF of decoupling capacitance on the ADR366B's output.

I understand the ADC draws high frequency current, and I fear the ADR366B voltage reference offers poor regulation in this frequency range.



2. According to the datasheet, the TRIM pin is to be left floating if unsed.

=> as my environement is pretty noisy, would it not be a good practice to add a decoupling capacitor (as this input leads directly to the bandgap transistors pair)?
if yes, I assume this capacitor would be in the 10 nF range and best placed between the TRIM and OUT pins?

Thank you very much for the feedback.

Best regards,
Gauthier Lemey