This paper describes an algorithm for Successive Approximation Register (SAR) ADCs with overlapping steps that allow comparison decision errors (due to, such as DAC incomplete settling) to be digitally corrected. We generalize this non-binary search algorithm, and clarify which decision errors it can digitally correct. This algorithm requires more SAR ADC conversion steps than a binary search algorithm, but we show that the sampling speed of an SAR ADC using this algorithm can be faster than that of a conventional binary-search SAR ADC -- because the latter must wait for the settling time of the DAC inside the SAR ADC.

A 1/2 frequency divider using resonant-tunneling hot electron transistors (RHETs) has been proposed and demonstrated. The circuit make the best use of negative differential conductance, a feature of RHETs, and contains one half transistors than used in conventional circuits. The RHETs were fabricated using self-aligned InGaAs RHETs and WSiN thin-film resistors on a single chip. The RHETs have an i-InGaAlAs/i-InGaAs collector barrier that improves the current gain at low collector-base voltages. Circuit operation was confirmed at 77 K.