Abstract: A click-noise suppression system having MOSFET transistor switches positioned between the preamplifiers and coupling capacitors of an audio system wherein the suppression system maintains the switches off when the system is turned on until a charging circuit increases the gate voltage of the switches. The switches quickly turn off and the coupling capacitors are discharged through discharge resistors when the system is turned off.

Abstract: A low power monolithic CMOS device incorporating functions to control power supply transition noise such as in audio circuits and systems. The digital control circuit incorporates MOSFETs that are maintained in an OFF state during normal operation and are turned ON only when system power is turned on or off to thus eliminate the need for bias voltages and maintain minimal quiescent current.

Abstract: A bi-directional transient voltage suppression (“TVS”) device (101) includes a semiconductor die (201) that has a first avalanche diode (103) in series with a first rectifier diode (104) connected cathode to cathode, electrically coupled in an anti-parallel configuration with a second avalanche diode (105) in series with a second rectifier diode (106) also connected cathode to cathode. All the diodes of the TVS device are on a single semiconductor substrate (301). The die has a low resistivity buried diffused layer (303) having a first conductivity type disposed between a semiconductor substrate (301) having the opposite conductivity type and a high resistivity epitaxial layer (305) having the first conductivity type. The buried diffused layer shunts most of a transient current away from a portion of the epitaxial layer between the first avalanche diode and the first rectifier diode, thereby reducing the clamping voltage relative to the breakdown voltage.