Abstract: An apparatus for reducing voltage surge while powering up an amplifier device, the amplifier device charging an input capacitance in at least one input line during the powering up, the charging being subject to a time constant established by the input capacitance in cooperation with an input resistance in the at least one input line, includes: a resistive load switchingly coupled with at least a portion of the input resistance in the at least one input line. The switchingly coupling is effected during at least a portion of the powering up.

Abstract: Latch-up preventing circuits and methods are provided for ESD protection cells. A method of preventing latch-up in an ESD protection cell is described which includes monitoring the ESD protection cell to detect the activation of the ESD protection cell in response to an ESD event. After detection of the activation of the ESD protection cell, the supply current to the ESD protection cell is turned off, preventing latch-up. Circuit embodiments are described in which ESD protection circuits include are provided with a detection and reset circuit. The circuit is adapted to turn off the supply current to the ESD protection cell upon the detection of the activation of the ESD cell.

Abstract: An apparatus for controlling output signals from an amplifier when changing state; the amplifier having input loci, output loci and a state locus, and changing state in response to a state controlling signal received at the state locus; includes: (a) a state sensing circuit coupled with the state locus that provides a state signal in response to the state controlling signal; (b) an input level unit coupled with the state sensing circuit and with a selected input locus, and setting a first input signal level at the selected input locus when the amplifier changes from a first state to a second state; and (c) an output level unit coupled with the state sensing circuit and with a selected output locus, and setting a first output signal level at the selected output locus when the amplifier changes from the first state to the second state.

Abstract: An apparatus for controlling output signals from an amplifier when changing state; the amplifier having input loci, output loci and a state locus, and changing state in response to a state controlling signal received at the state locus; includes: (a) a state sensing circuit coupled with the state locus that provides a state signal in response to the state controlling signal; (b) an input level unit coupled with the state sensing circuit and with a selected input locus, and setting a first input signal level at the selected input locus when the amplifier changes from a first state to a second state; and (c) an output level unit coupled with the state sensing circuit and with a selected output locus, and setting a first output signal level at the selected output locus when the amplifier changes from the first state to the second state.