Abstract: A high resolution analog to digital (A/D) converter amplifies and filters a magnitude difference between a pulse width modulated offset voltage and an input voltage to produce an amplified filtered difference voltage, the duty cycle of offset voltage modulation being adjusted such that the magnitude of the difference voltage is within a narrow input voltage range of a recirculating remainder A/D converter. The amplified, filtered difference voltage is converted to representative digital data by the recirculating remainder A/D converter. A microprocessor, which controls the offset voltage, combines the result with the magnitude of the offset voltage to produce a comparatively high resolution digital representation of the input voltage.

Abstract: A probe for a logic analyzer includes a replacement plug assembly comprising those portions of probe equipment which must be specifically adapted to accommodate a selected microprocessor, and a buffer probe assembly comprising those portions of probe equipment which are adapted for use with a wide variety of microprocessors. The replacement plug assembly and the buffer probe assembly are mechanically joined and electrically coupled by a square pin connector so that the replacement plug assembly may be removed from the probe and replaced with a differently configured replacement plug assembly when a different microprocessor is to be probed. Thus only a portion of the probe is changed to retarget the probe for different microprocessors.