Universal Definition for "No Connect" or "NC"?

Hi, David.

Thank you for using ADI products. Regarding your question, the "NC" or "No connect" pins have no internal connections. These pins are provision for improvement for the part's derivative. This means that the "NC" pins of AD8624 in LFCSP maybe used as a reference pin, enable pin, common-mode pin or other additional pinout in the next generation of AD8624. If these "NC" pins have an assigned label such as REF pin, etc, then these pins have already an internal connection.

As additional information, the two "NC" pins of AD8624 were only added to comply with the 16-lead LFCSP standard. Also, the two "NC" pins of ADR445 were added to comply with the 8-lead SOIC and MSOP standard.

Hope this helps.

Regards,

Anna

Hi David,

NC pins are sometimes found at devices which are in packages that have more pins than actually are used by the device. Other devices still might have internal connections to pins shown as NC, which are used i.e. for testing or trimming purposes, or such pins are intentionally kept free for another similar device which has an additional connection to such a pin. This is not specified in the data sheet.

Therefore, if a pin is shown as NC, this means, that a user should not connect anything to this pin. The pin is not contained in the specification of the device. Therefore, nothing can be guaranteed if such a pin is connected externally. Always only connect pins which are described and specified in a device's data sheet. This is what Analog Devices specify, test and guarantee. Everything else is beyond what is specified by Analog Devices and Analog Devices will not be liable for anything that might happen if such a pin is not left open.