Abstract: A circuit device having data retention latches utilizes a test interface and system test controller to control one or more components of the circuit device to ensure proper conditions for testing the data retention latches. The data retention latches each include a scan component that is part of a scan chain, a first latching component that is powered in a first voltage domain and a second latching component that is powered in a second voltage domain, where one of the voltage domains can be effectively shut down when the circuit device is placed in a low-voltage mode. The system test controller can control a scan controller used to scan test data in and out of the scan chain. The system test controller further can control a power controller used to manage a power down sequence and a power up sequence so as to ensure that the data retention latches are not placed in spurious states.