Frequently Asked Question
The AD9510 datasheet says to use an external pull-up resistor on the FUNCTION pin. Why do I need this and what range of resistors will work?
The AD9510/11/12 have a 30k ohm internal pull-down resistor on the FUNCTION pin. If this pin is not driven externally, it sits at a low logic level. The default function of the FUNCTION pin is RESETB. This means that the part will not function until this pin is driven high. This pin can be tied directly to the positive supply (or a small value resistor <10k) if not used. However, if it is used it must be actively driven.