Abstract: A semiconductor device includes an active region, a LOCOS region formed within the active region and that extends vertically above a top surface of the active region, a gate region formed above the top surface of the active region, and a polysilicon resistor having a bottom surface that is offset vertically and physically isolated from a top surface of the LOCOS region. The active region includes a source region laterally disposed from the gate region, a drain region laterally disposed from the gate region, and a drift region laterally disposed between the gate region and the drain region. The polysilicon resistor is formed above the drift region. The active region further includes a first charge balance region formed in the active region below the drift region.

Abstract: An electronic device includes a semiconductor substrate and a bidirectional transistor switch formed on the substrate, the bidirectional switch including a first source node, a second source node and a common drain node. A first transistor is formed on the substrate and includes a first source terminal, a first drain terminal and a first gate terminal, wherein the first source terminal is connected to the substrate, the first drain terminal is connected to the first source node and the first gate terminal is connected to the second source node. A second transistor is formed on the substrate and includes a second source terminal, a second drain terminal and a second gate terminal, wherein the second source terminal is connected to the substrate, the second drain terminal is connected to the second source node and the second gate terminal is connected to the first source node.

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: An electronic device includes a semiconductor substrate and a bidirectional transistor switch formed on the substrate, the bidirectional switch including a first source node, a second source node and a common drain node. A first transistor is formed on the substrate and includes a first source terminal, a first drain terminal and a first gate terminal, wherein the first source terminal is connected to the substrate, the first drain terminal is connected to the first source node and the first gate terminal is connected to the second source node. A second transistor is formed on the substrate and includes a second source terminal, a second drain terminal and a second gate terminal, wherein the second source terminal is connected to the substrate, the second drain terminal is connected to the second source node and the second gate terminal is connected to the first source node.

Abstract: An electronic device includes a semiconductor substrate and a bidirectional transistor switch formed on the substrate, the bidirectional switch including a first source node, a second source node and a common drain node. A first transistor is formed on the substrate and includes a first source terminal, a first drain terminal and a first gate terminal, wherein the first source terminal is connected to the substrate, the first drain terminal is connected to the first source node and the first gate terminal is connected to the second source node. A second transistor is formed on the substrate and includes a second source terminal, a second drain terminal and a second gate terminal, wherein the second source terminal is connected to the substrate, the second drain terminal is connected to the second source node and the second gate terminal is connected to the first source node.

Abstract: A semiconductor device includes an active region, a LOCOS region formed within the active region and that extends vertically above a top surface of the active region, a gate region formed above the top surface of the active region, and a polysilicon resistor having a bottom surface that is offset vertically and physically isolated from a top surface of the LOCOS region. The active region includes a source region laterally disposed from the gate region, a drain region laterally disposed from the gate region, and a drift region laterally disposed between the gate region and the drain region. The polysilicon resistor is formed above the drift region. The active region further includes a first charge balance region formed in the active region below the drift region.

Abstract: An active clamp circuit for a power converter having a transformer includes a switch having a drain node, a gate node, and a source node, the drain node configured to be connected to a first terminal of a primary winding of the transformer, a capacitor having a first terminal connected to the source node, and a second terminal to be connected to a second terminal of the primary winding, a gate driver coupled to the gate node to control the switch and having a high-side input node and a low-side input node, the low-side input node being coupled to the first terminal of the capacitor, and a voltage regulator to: i) receive an input voltage from the second terminal of the capacitor, and ii) provide a regulated voltage to the high-side input node using the input voltage and being of a sufficient voltage level to control the switch.

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: 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: An active clamp circuit for a power converter having a transformer includes a switch having a drain node, a gate node, and a source node, the drain node configured to be connected to a first terminal of a primary winding of the transformer, a capacitor having a first terminal connected to the source node, and a second terminal to be connected to a second terminal of the primary winding, a gate driver coupled to the gate node to control the switch and having a high-side input node and a low-side input node, the low-side input node being coupled to the first terminal of the capacitor, and a voltage regulator to: i) receive an input voltage from the second terminal of the capacitor, and ii) provide a regulated voltage to the high-side input node using the input voltage and being of a sufficient voltage level to control the switch.

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: An active clamp circuit for a power converter having a transformer includes a switch having a drain node, a gate node, and a source node, the drain node configured to be connected to a first terminal of a primary winding of the transformer, a capacitor having a first terminal connected to the source node, and a second terminal to be connected to a second terminal of the primary winding, a gate driver coupled to the gate node to control the switch and having a high-side input node and a low-side input node, the low-side input node being coupled to the first terminal of the capacitor, and a voltage regulator to: i) receive an input voltage from the second terminal of the capacitor, and ii) provide a regulated voltage to the high-side input node using the input voltage and being of a sufficient voltage level to control the switch.

Abstract: Determine the duty cycle of the pulse width modulation signal to derive the voltage value of the alternating current voltage when the power supply is in the peak power working status. The voltage value of the alternating current voltage is determined as high if the duty cycle of the pulse width modulation signal is lower than the predetermined duty cycle. At this time, the limit detection voltage of the pulse width modulation controller is suppressed to protect the transistor switch, and the power supply can still provide the load apparatus with enough power. The power supply does not need any alternating current voltage detection circuit. The voltage value of the alternating current voltage is derived by determining the duty cycle of the pulse width modulation signal.

Abstract: Determine the duty cycle of the pulse width modulation signal to derive the voltage value of the alternating current voltage when the power supply is in the peak power working status. The voltage value of the alternating current voltage is determined as high if the duty cycle of the pulse width modulation signal is lower than the predetermined duty cycle. At this time, the limit detection voltage of the pulse width modulation controller is suppressed to protect the transistor switch, and the power supply can still provide the load apparatus with enough power. The power supply does not need any alternating current voltage detection circuit. The voltage value of the alternating current voltage is derived by determining the duty cycle of the pulse width modulation signal.

Abstract: Methods for flyback converters are provided. The method, adopted by a flyback converter circuit including a transformer, including: determining an output voltage output from a secondary circuit of the transformer; feeding a feedback voltage based on the output voltage from the secondary circuit back to a primary circuit of the transformer; increasing a current limit and a switching frequency of a primary current with the feedback voltage; and supplying the primary current to a primary winding of the transformer.

Abstract: A power supply with low voltage protection provides an output voltage. The power supply includes a driving switch and a control unit. The control unit generates a control signal with a duty cycle. The driving switch receives the control signal to drive the output voltage of the power supply. The control unit enables an under-voltage protection mode when the control unit detects that the output voltage is less than a threshold output voltage value and the duty cycle is less than a maximum duty cycle value. The control unit disables the under-voltage protection mode when the control unit detects that the output voltage is less than the threshold output voltage value and the duty cycle reaches to the maximum duty cycle value.

Abstract: A control circuit for controlling a power supply is revealed. The control circuit is used to generate a switching signal for switching the power supply. The control circuit has a detection terminal for detecting a status of the power supply. A first protection circuit is coupled to the detection terminal and to receive a first detection signal via the detection terminal, and the first protection generates a limit signal in response to the first detection signal, for limiting output of the power supply. A second protection circuit is coupled to the detection terminal and to receive a detection signal via thereto, and the second protection generates a protecting signal, for cutting off the output of the power supply, in response to the first detection signal.

Abstract: A method providing short-circuit protection and a flyback converter utilizing the same wire are disclosed. The a method, adopted by a flyback converter, includes a transformer, including generating a feedback voltage according to an output voltage output from a secondary winding of the transformer; controlling a primary current through a primary winding of the transformer based on the feedback voltage; determining a sense voltage according to the primary current; determining a short circuit based on the sense voltage; setting the primary current according to a short-circuit sense voltage limit when a short circuit occurs; and setting the primary current according to a normal sense voltage limit when a short circuit does not occur.

Abstract: A power converter is provided. A transformer includes a primary winding for providing a primary voltage according to an input voltage, a secondary winding for providing a secondary voltage according to the primary voltage and an auxiliary winding for providing a reflection voltage according to the secondary voltage. A first switch coupled between the primary winding of the transformer and a ground has a control terminal for receiving a first control signal. A second switch coupled to the secondary winding has a control terminal for receiving a second control signal. A controller provides the first control signal to switch the first switch, so as to control the transformer to provide the secondary voltage. The controller provides the second control signal to switch the second switch according to the first control signal and the reflection voltage, so as to provide an output voltage in response to the secondary voltage.

Abstract: Methods for flyback converters are provided. The method, adopted by a flyback converter circuit including a transformer, including: determining an output voltage output from a secondary circuit of the transformer; feeding a feedback voltage based on the output voltage from the secondary circuit back to a primary circuit of the transformer; increasing a current limit and a switching frequency of a primary current with the feedback voltage; and supplying the primary current to a primary winding of the transformer.