Abstract: A transceiver (100) for TTL and RS232 communication with automatic sensing (130) of the type of input and adjustment of the output to correspond together with current stealing (131) from the input communication lines to provide extreme voltages for transmission. Hysteresis and surge suppression are built into the sensing.

Abstract: Jitter attenuators (100) with a phase detector (104) to control a crystal oscillator to remove jitter wherein the phase detector includes both a sequential phase/frequency detector (200) of low transistor count and an arrangement of two sequential phase/frequency detectors (198 and 200) to increase gain and two drivers for the crystal oscillator.

Abstract: An integrated circuit which, for ESD protection at an input pad, uses a split series resistor, with two clamping diodes of different types. By splitting up the series resistance in this fashion, some impedance is provided before the first hard diode, without causing an excessive total impedance. When a positive-going transient appears at the pad, the current is limited only by a moderate impedance (which saves area); when a negative-going transient appears, the current is limited by a much higher impedance (which allows a lower leakage current to be achieved).