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Frequently Asked Question

Is it ok for me to connect the same power supply to both the charge pump and distribution power supply pins?

The clock distribution section is powered by 3.3V. The max charge pump supply setting is 5V to accommodate 5V VCOs and VCXOs devices. If the designer sets the charge pump supply at 3.3V and good supply decoupling exist, powering the two circuits with one supply would be left up to the designer's discretion. It is always nice to reduce supply domains, however the charge pump is a sensitive node that should be free from excessive noise and switching which could easily transfer to the output. It should be evaluated case by case.