Abstract: An apparatus includes a high-pass filter circuit configured to receive a drain-source voltage from a drain node of a synchronous rectifier switch at a secondary-side of a power converter and to generate a filtered drain-source voltage using the received drain-source voltage. A current comparison circuit of the apparatus is configured to receive a current indicative of a current through the synchronous rectifier switch and to generate a current comparison signal using the received current. An auto-tuning controller of the apparatus is configured to turn the synchronous rectifier switch on upon determining a body diode conduction of the synchronous rectifier switch, commence an auto-tuned delay upon determining that the current through the synchronous rectifier switch has changed direction, turn the synchronous rectifier switch off upon expiration of the auto-tuned delay, and update, during a detection window of time, a duration of the auto-tuned delay based on the filtered drain-source voltage.

Abstract: A method involves controlling, for a duration of a first modulation period, a first average off-time of a main switch of a power converter such that the first average off-time of the main switch corresponds to a first intermediate valley number of multiple intermediate valley numbers, an average of the intermediate valley numbers corresponding to a target number of valleys of a resonant waveform at a drain node of the main switch. A second intermediate valley number of the intermediate valley numbers is selected upon expiration of the first modulation period. A difference of the second intermediate valley number and the first intermediate valley number is equal to a fractional valley number offset. A second average off-time of the main switch is controlled for a duration of a second modulation period such that the second average off-time of the main switch corresponds to the second intermediate valley number.

Abstract: A power transistor is switched on and off with an on-time that is held constant and an off-time that is varied. When the off-time is detected to be less than a threshold value that is greater than a minimum off-time limit, the on-time is extended. Then the power transistor is switched on and off with the extended on-time that is held constant and the off-time that varies.

Abstract: An improved laterally diffused MOSFET (LDMOS) device enables an ability to tune some device parameters independently of other device parameters and/or provides a device architecture with component dimensions that significantly improve device performance. The LDMOS device includes a stepped gate having a first portion with a thin gate insulator over a body region and a second portion with a thick gate insulator over part of a drift region. In some embodiments, a gate shield is disposed over another part of the drift region to reduce a gate-drain capacitance of the LDMOS device. In some embodiments, the LDMOS device has a specific resistance (Rsp) of about 5-8 mOhm*mm2, a gate charge (Qg) of about 1.9-2.0 nC/mm2, and an Rsp*Qg product figure of merit of about 10-15 mOhm*nC.

Abstract: A width of a voltage pulse signal is directly proportional to a difference between first and second resistances in a pulse generator. The voltage pulse signal is generated with a ramp signal, two reference voltages, and two comparators. The first reference voltage is generated with the first resistance and a first current, and the second reference voltage is generated with the second resistance and a second current. The first comparator produces a first comparator output in response to the first reference voltage and the ramp signal, and the second comparator produces a second comparator output in response to the second reference voltage and the ramp signal. A logic circuitry generates the voltage pulse signal in response to the two comparator outputs.

Abstract: Disclosed is a device including a first finger of a plurality of lead fingers of a lead frame connected to a first flag. A second finger of the plurality of lead fingers of the lead frame is connected to a second flag. A semiconductor die is coupled to the lead frame. An encapsulant covers the semiconductor die, the lead frame, and a first end of the plurality of lead fingers, and excludes the first flag and the second flag. The first flag and the second flag are separated and electrically isolated from one another by the encapsulant.

Abstract: Embodiments of the disclosure include a switch having an on-state resistance that varies based on a temperature coefficient of the switch and an overcurrent protection circuit coupled to the switch and having an adjustable overcurrent threshold level determined based on an adjustable voltage generated by the overcurrent protection circuit, the adjustable voltage generated based on the temperature coefficient of the switch.

Abstract: A charge pump having only NMOS devices charges a plurality of capacitors to a parallel charged voltage level by electrically connecting the capacitors in parallel between an input voltage node and a ground by activating a plurality of first NMOS transistor switches and a plurality of second NMOS transistor switches and deactivating a plurality of third NMOS transistor switches. The charge pump then generates a series capacitor output voltage level at a capacitor series output node by electrically connecting and discharging the capacitors in series between the input voltage node and the capacitor series output node by activating the third NMOS transistor switches and deactivating the first NMOS transistor switches and the second NMOS transistor switches.

Abstract: A wireless power transmission system includes a transmitter coil in a power transmitting circuit and a receiver coil in a power receiving circuit. Either the receiver coil serves as a current-limiting coil or the system also includes a current-limiting coil that is separate from the transmitter coil and the receiver coil. The transmitter coil generates a magnetic field from a transmitter current flowing therethrough. The current-limiting coil generates an opposing magnetic field from the magnetic field, which limits the transmitter current, in a current-limiting mode.

Abstract: An improved ramp generator enables a very high degree of linearity in an output voltage ramp signal. Output ramps of the output voltage ramp signal are alternatingly produced from two preliminary ramp signals during alternating time periods. Preliminary ramps are produced at different preliminary ramp nodes that are alternatingly connected to an output node. The preliminary ramps continuously ramp during and in some cases beyond, e.g., before and/or after, the time periods. In some embodiments, switches alternatingly connect two capacitors to at least one current source, a reset voltage source, and the output node to alternatingly produce the preliminary ramps.

Abstract: An improved laterally diffused MOSFET (LDMOS) device enables an ability to tune some device parameters independently of other device parameters and/or provides a device architecture with component dimensions that significantly improve device performance. The LDMOS device includes a stepped gate having a first portion with a thin gate insulator over a body region and a second portion with a thick gate insulator over part of a drift region. In some embodiments, a gate shield is disposed over another part of the drift region to reduce a gate-drain capacitance of the LDMOS device. In some embodiments, the LDMOS device has a specific resistance (Rsp) of about 5-8 mOhm*mm2, a gate charge (Qg) of about 1.9-2.0 nC/mm2, and an Rsp*Qg product figure of merit of about 10-15 mOhm*nC.

Abstract: Various methods and devices that involve body contacted transistors are disclosed. An exemplary method comprises forming a gate on a planar surface of a semiconductor wafer. The gate covers a channel of a first conductivity type that is opposite to a second conductivity type. The method also comprises implanting a body dose of dopants on a source side of the gate using the gate to mask the body dose of dopants. The body dose of dopants spreads underneath the channel to form a deep well. The body dose of dopants has the first conductivity type. The method also comprises implanting, subsequent to implanting the body dose of dopants, a source dose of dopants on the source side of the gate to form a source. The method also comprises forming a source contact that is in contact with the deep well at the planar surface of the semiconductor wafer.

Abstract: A width of a voltage pulse signal is directly proportional to a difference between first and second resistances in a pulse generator. The voltage pulse signal is generated with a ramp signal, two reference voltages, and two comparators. The first reference voltage is generated with the first resistance and a first current, and the second reference voltage is generated with the second resistance and a second current. The first comparator produces a first comparator output in response to the first reference voltage and the ramp signal, and the second comparator produces a second comparator output in response to the second reference voltage and the ramp signal. A logic circuitry generates the voltage pulse signal in response to the two comparator outputs.

Abstract: A method involves determining a target number of valleys of a resonant waveform at a drain node of a main switch of a power converter. The target number of valleys corresponds to a desired off-time of the main switch. A first intermediate valley number of a series of intermediate valley numbers is selected. An average of the series of intermediate valley numbers corresponds to the target number of valleys. A first average off-time of the main switch is controlled, for a duration of a first modulation period, such that the first average off-time corresponds to the first intermediate valley number. Upon expiration of the first modulation period, a second intermediate valley number of the intermediate valley numbers is selected. A second average off-time of the main switch is controlled, for a duration of a second modulation period, such that the second average off-time corresponds to the second intermediate valley number.

Abstract: An improved circuit or method generates first and second initial pulses that do not overlap. First and second drive pulses are generated based on the first and second initial pulses, respectively. A first transistor is turned on with the first drive pulses. A second transistor is turned on with the second drive pulses. A current flows in response to an on-time state of the first transistor overlapping with an on-time state of the second transistor. A delay of the second drive pulses is decreased based on a time of the current flow overlapping with one of the first initial pulses; and the delay of the second drive pulses is increased based on the time of the current flow overlapping with one of the second initial pulses.

Abstract: Disclosed is a device including a lead frame having a body with a top surface and a bottom surface and lead fingers. Each lead finger has a first end and a second end. A semiconductor die is coupled to the body. A first flag is a first exposed portion of the body and integral with the first end of a first lead finger. The first flag and the first lead finger are a continuous material. A second flag is a second exposed portion of the body and integral with the first end of a second lead finger. The second flag and the second lead finger are a continuous material. An encapsulant covers the die, the bottom surface of the body, the first end of the lead fingers and a portion of the top surface of the body. The flags are separated and electrically isolated from one another by the encapsulant.

Abstract: A power converter includes an input node on an input side of the power converter, an output node on an output side of the power converter, a switch coupled to the input node and having a switch control node, an inductor coupled to the switch and to the output node, and a feedback compensation and control circuit between the output node and the switch control node. The feedback compensation and control circuit includes two or more programmable resistors to adjust one or more gains of i) a proportional-integral-derivative portion, and ii) a bandpass filter portion of the feedback compensation and control circuit. The feedback compensation and control circuit receives an output voltage from the output node and generates a compensated feedback signal based on the output voltage from the output node and the one or more gains, the switch control node being controlled based on the compensated feedback signal.

Abstract: An apparatus for turning off a cascode amplifier having a common-base transistor and a common-emitter transistor is disclosed that includes the cascode amplifier, a feedback circuit, and a bias circuit. The feedback circuit is configured to receive a collector-voltage from the collector of the common-emitter transistor when the common-emitter transistor is switched to a first OFF state and produce a first feedback signal. The collector-voltage is equal to an emitter voltage of the common-base transistor and the collector-voltage increases in response to switching the common-emitter transistor to the first OFF state. The bias circuit is configured to receive the first feedback signal and produce a bias-voltage. A first base-voltage is produced from the bias-voltage. The cascode amplifier is configured to receive the first base-voltage and a second base-voltage. The common-base transistor is configured to switch to a second OFF state in response to receiving the second base-voltage.

Abstract: Embodiments of the disclosure include a switch having an on-state resistance that varies based on a temperature coefficient of the switch and an overcurrent protection circuit coupled to the switch and having an adjustable overcurrent threshold level determined based on an adjustable voltage generated by the overcurrent protection circuit, the adjustable voltage generated based on the temperature coefficient of the switch.

Abstract: An improved ramp generator enables a very high degree of linearity in an output voltage ramp signal. Output ramps of the output voltage ramp signal are alternatingly produced from two preliminary ramp signals during alternating time periods. Preliminary ramps are produced at different preliminary ramp nodes that are alternatingly connected to an output node. The preliminary ramps continuously ramp during and in some cases beyond, e.g., before and/or after, the time periods. In some embodiments, switches alternatingly connect two capacitors to at least one current source, a reset voltage source, and the output node to alternatingly produce the preliminary ramps.