Abstract: A detector circuit may detect a peak value of at least one input voltage and may provide the peak value as an output for use by other circuitry capable of being coupled to the detector circuit. Pairs of differential inputs may be employed, using n-channel transistors (in one example), and using diodes to capture the peak at a shared output node. Each differential pair has two constant current devices connecting the source/drain paths to the terminal of a voltage supply. This circuit enables the use of high input voltages which may be at or near the upper power supply (e.g., V.sub.DD). The circuit is in effect a negative peak detector, capturing the most negative value of at least one input level and holding that level, with a slow leakage of the held value back toward the upper voltage supply with a time constant that is generally set much slower than the input signal transition frequency. A similar circuit may be implemented using p-channel transistors in the differential pairs, to detect positive peaks.

Abstract: A driver circuit is presented for producing particular output voltage levels at high speeds using a current switching technique. The circuit employs driver transistors connected in series between switchable current sources. The driver transistors switch current within the current sources through a resistor coupled between an output of the driver circuit and a reference terminal voltage. Switching the current occurs in rapid fashion within an opened loop arrangement. The switchable current sources are configured so that current is present through the current sources whenever a corresponding driver transistor is turned on. Current through the current sources, as switched through the resistor separating the reference terminal voltage and the driver output, is regulated by a closed loop replica circuit. The replica circuit may include an opamp whose output operably produces the regulated current via feedback from the current path to an input of the opamp.