A device testing method and interface includes receiving a first command and a second command, selectively combining at least a portion of the second command with at least a portion of the first command to generate a test command, and transmitting the test command to the device. The chip is arranged on the carrier and electrically connected to the carrier, while the mold compound covers the chip and one surface of the carrier. A second Class AB amplifier circuit having an input that communicates with an output of the bias circuit and that generates an output signal. As the closure is applied down on the container, the locking lugs engage notches formed in the undersides of the projections and internal cam surfaces on the cam lugs engage external cam surfaces formed on projections disposed around the open end of the container.