A power source switch circuit and an operation method thereof are provided. The power source switch circuit may include a switch circuit that includes a first switch configured switch a supply of a voltage from a first power supply circuit to a power supply terminal of a power amplifier, and a second switch configured to switch a supply of a voltage from a second power supply circuit to the power supply terminal of the power amplifier; and a switch controller configured to control the switch circuit to set the first switch and the second switch in a turned-on state during a first period when the first switch is turned off and the second switch is turned on.

An apparatus includes a first leg having a plurality of transistors connected in series between a first node and a second node. Each of the plurality of transistors includes a respective body diode. The apparatus further includes a second leg connected between the first node and the second node and in parallel to the series connection of the plurality of transistors of the first leg. The second leg includes a first transistor. The second leg has lower reverse recovery losses relative to the first leg.

Laser driver designs that aim to reduce or eliminate the problem of fault laser firing are disclosed. Various laser driver designs presented herein are based on providing a current dissipation path that is configured to start providing a resistance for dissipating at least a portion, but preferably substantially all, of the negative current from the laser diode. Dissipating at least a portion of the negative current may decrease the unintentional increase of the voltage at the input to the laser diode and, therefore, reduce the likelihood that fault laser firing will occur. A control logic may be used to control the timing of when the current dissipation path is activated (i.e., provides the resistance to dissipate the negative current from the laser diode) and when it is deactivated.

An aspect relates to an apparatus including a first and second power rails; a first set of power switch cells coupled to the first and second power rails, the first set of power switch cells being cascaded from an output to an input of a control circuit; and a second set of power switch cells coupled to the first and second power rails, the second set of power switch cells being coupled to one of a pair of cells of the first set, the first output, and the first input of the control circuit. Another aspect relates to a method including propagating a control signal via a first set of cascaded power switch cells to sequentially couple a first power rail to a second power rail; and propagating the control signal via a second set of power switch cells coupled between a pair of cells of the first set.

An active gate driver suitable for activating an electronic switch of an electric motor. The active gate driver includes a pull up branch, a pull down branch and a current and voltage feedback from an output of the active gate driver to at least one input of the active gate driver, wherein the current and voltage feedback is common to both the pull up branch and the pull down branch.

A digital step attenuator (DSA) cell and related method are provided. The DSA cell includes a first branch comprising a first resistor connected, at a first side, to an input port and, at a second side, to an output port; a second resistor connected, at a first side, to the first resistor and, at a second side, to a first transistor and a third resistor connected, at a first side, to the first resistor and, at a second side, to a second transistor. Also included in the DSA cell is a second branch, in a parallel configuration with the first resistor, that includes a fourth resistor and a third transistor. Also included is a third branch, in a parallel configuration with the first resistor, that includes a fourth transistor. The first transistor, the second transistor, the third transistor, and the fourth transistor are configured to be operated independently.

An electromagnetic interference regulator by use of capacitive parameters of the field-effect transistor for detecting the induced voltage and the induced current of the field-effect transistor to determine whether the operating frequency of the field-effect transistor is within the preset special management frequency of electromagnetic interference. When the basic frequency and the multiplied frequency exceed the limit, the content of the external capacitor unit can be adjusted to assist the products using field-effect transistors to maintain excellent electromagnetic interference adjustment capabilities under various loads, thereby optimizing the characteristics of electromagnetic interference.

Disclosed herein are switching or other active FET configurations that implement a branch design with one or more interior FETs of a main path coupled in parallel with one or more auxiliary FETs of an auxiliary path. Such designs include a circuit assembly for performing a switching function that includes a branch with a plurality of auxiliary FETs coupled in series and a main FET coupled in parallel with an interior FET of the plurality of auxiliary FETs. The body nodes of the FETs can be interconnected and/or connected to a body bias network. The body nodes of the FETs can be connected to body bias networks to enable individual body bias voltages to be used for individual or groups of FETs.

A digital step attenuator (DSA) cell and related method are provided. The DSA cell includes a first branch comprising a first resistor connected, at a first side, to an input port and, at a second side, to an output port; a second resistor connected, at a first side, to the first resistor and, at a second side, to a first transistor and a third resistor connected, at a first side, to the first resistor and, at a second side, to a second transistor. Also included in the DSA cell is a second branch, in a parallel configuration with the first resistor, that includes a fourth resistor and a third transistor. Also included is a third branch, in a parallel configuration with the first resistor, that includes a fourth transistor. The first transistor, the second transistor, the third transistor, and the fourth transistor are configured to be operated independently.

A driver circuit for switching edge modulation of a power switch. The driver circuit includes a first driver circuit input including a downstream input node, and a power switch including an upstream first gate node. A charging path including a charging resistor is situated between the input node and the first gate node. A discharging path including a discharging resistor is situated between the input node and the first gate node. A gate path is situated between the input node and the first gate node. A power switch transistor, whose gate is connected to the first gate node, is provided. A gate path includes a gate resistor. The driver circuit is configured so that, during a switching process of the power switch, the gate path is temporarily short-circuited either via the charging path or the discharging path, to increase the slope of the switching behavior of the power switch.