Abstract: A system tests analog and mixed signal IC devices using an FFT algorithm, supported by a non-iterative Fast Fourier Transform (FFT) coherency analysis algorithm to establish FFT sample-set coherency. A test signal is input into the IC device, and an output signal from the IC device is analyzed using the FFT algorithm. The non-iterative FFT coherency analysis algorithm uses only one “given” value and two approximated values related to a test signal. Based on these given and approximated values, the correct set of all four values required for proper testing of the IC device is determined in a single pass, without the need for multiple iterations.

Abstract: A two-wheeled toy includes a central housing supported on a rotatable shaft between the wheels. The diameter of the wheels is larger than the housing, with a figure mounted on the housing extending above the wheels. The housing includes a miniature electric motor, gearing, batteries and a switch to activate the motor and drive the wheels. The batteries are mounted in the bottom of the housing to provide a weight and low center of gravity to maintain the housing and figure in an upright position during movement. The figure limits counter-rotation of the housing about the shaft when the wheels start to turn and move forward. The shaft extends outwardly from the wheels and provides a stop which prevents the wheels from falling sideways. The wheels may also be driven independently by separate motors and shafts and may be remotely controlled to permit turning and movement in different directions while the housing remains upright.