Abstract: A synchronous rectification controller configured to control a synchronous rectification transistor is provided on the secondary side of an insulated synchronous rectification DC/DC converter. A DRAIN pin receives the drain voltage VDS2 of the synchronous rectification transistor. A pulse generator generates a pulse signal S11 based on the voltage at the DRAIN pin. A driver drives the synchronous rectification transistor based on the pulse signal S11. Upon detecting an open-circuit fault of the DRAIN pin, an abnormality detection circuit asserts an abnormality detection signal S13.

Abstract: A male member and tool changer for downsizing and preventing damage to proximity sensors; a male member includes a cam adapted to pivot between an engagement position at which the cam engages with a lock pin of a female member and a disengagement position at which the cam moves out of the engagement, and a cylinder unit adapted to pivot the cam between the engagement position and the disengagement position. A first proximity sensor and the second proximity sensor are assembled onto a cylinder sidewall of the cylinder unit and first and second detection surfaces of the proximity sensors are revealed in a cylinder chamber. The first detection surface is placed at a position facing on a piston when the cam is located at the disengagement position and the second detection surface is placed at a position facing on the piston when the cam is located at the engagement position.

Abstract: An isolated DC/DC converter includes a transformer having a first winding and a secondary winding, a switching transistor connected to the primary winding of the transformer, a rectifier element connected to the secondary winding of the transformer, a photocoupler, a feedback circuit configured to drive a light emitting element on an input side of the photocoupler by a forward current corresponding to an error between an output voltage of the DC/DC converter and a target voltage of the DC/DC converter, a conversion circuit configured to convert a collector current flowing in a light receiving element on an output side of the photocoupler into a feedback voltage having a negative correlation with the collector current, a pulse signal generator configured to generate a pulse signal corresponding to the feedback voltage, and a driver configured to drive the switching transistor depending on the pulse signal.

Abstract: When a pulse generator detects that a switching transistor on a primary side of a DC/DC converter turns off, the pulse generator sets a pulse signal S1 to an on level configured as an instruction to turn on a synchronous rectification transistor. When the pulse generator detects that the current that flows through the secondary winding of a transformer becomes substantially zero, the pulse generator sets the pulse signal S1 to an off level configured as an instruction to turn off the synchronous rectification transistor. After a predetermined time-up period elapses after the detection of the turn-on of the switching transistor, a forced turn-off circuit forcibly turns off the synchronous rectification transistor.

Abstract: An insulated DC/DC converter includes: a transformer; a switching transistor; a rectifier circuit; a photocoupler; a feedback circuit configured to drive a light emitting element of the photocoupler such that an output voltage of the DC/DC converter approaches a target voltage; a primary side controller having a feedback terminal which is connected to a light receiving element of the photocoupler and receives a feedback signal from the photocoupler, a zero current detection terminal which receives a zero current detection signal corresponding to a voltage generated at one end of an auxiliary winding of the transformer, and a pulse modulator of a quasi-resonant mode configured to generate a pulse signal depending on the feedback signal and the zero current detection signal; and a starting control circuit which, in start-up of the DC/DC converter, electrically affects the zero current detection terminal such that an OFF time of the switching transistor lengthens.

Abstract: An external circuit element RSET is connected in use to an SET terminal. A synchronous rectification controller generates a pulse signal Si based on a control time determined according to the state of the SET terminal. A driver switches on and off the synchronous rectification transistor according to the pulse signal S1. An abnormal state detection circuit is capable of detecting an open-circuit state and/or a short-circuit state that can occur in the SET terminal. When the abnormal state detection circuit detects such an open-circuit state and/or short-circuit state, the abnormal state detection circuit asserts a detection signal S11. When the detection signal S11 is asserted, a primary-side controller arranged on the primary side of the DC/DC converter is instructed to suspend the switching operation of a switching transistor.

Abstract: A secondary controller drives a light emitting element of a photocoupler such that a detection voltage VOUTS corresponding to an output voltage VOUT generated in an output capacitor C approximates to a reference voltage VREF. A primary controller controls a switching transistor M according to a feedback signal VFB. A protection circuit is activated and drives the light emitting element of the photocoupler when detecting an abnormal state. An auxiliary power supply circuit includes a power supply capacitor C provided separately from the output capacitor C and supplies a power supply voltage VCC to the protection circuit and an anode of the light emitting element of the photocoupler.

Abstract: A synchronous rectifying controller on secondary side of insulating synchronous rectifying converter to control synchronous rectifying transistor, comprising: first comparator to compare drain voltage of the transistor with first negative threshold voltage, and assert set signal based on the comparison of them; second comparator to compare drain voltage with second negative threshold voltage, and assert reset signal based on the comparison of them; third comparator to compare drain voltage with third positive threshold voltage, and assert release signal based on the comparison of them; control circuit set in response to the assertion of the set signal and to adjust control pulse to have ON level, and reset in response to the assertion of the reset signal and to adjust the control pulse to have OFF level; and driver to drive the transistor, wherein set operation of the control circuit is inhibited until the release signal is asserted.

Abstract: An external circuit element RSET is connected in use to an SET terminal. A synchronous rectification controller generates a pulse signal S1 based on a control time determined according to the state of the SET terminal. A driver switches on and off the synchronous rectification transistor according to the pulse signal S1. An abnormal state detection circuit is capable of detecting an open-circuit state and/or a short-circuit state that can occur in the SET terminal. When the abnormal state detection circuit detects such an open-circuit state and/or short-circuit state, the abnormal state detection circuit asserts a detection signal S11. When the detection signal S11 is asserted, a primary-side controller arranged on the primary side of the DC/DC converter is instructed to suspend the switching operation of a switching transistor.

Abstract: A secondary controller drives a light emitting element of a photocoupler such that a detection voltage VOUTS corresponding to an output voltage VOUT generated in an output capacitor C approximates to a reference voltage VREF. A primary controller controls a switching transistor M according to a feedback signal VFB. A protection circuit is activated and drives the light emitting element of the photocoupler when detecting an abnormal state. An auxiliary power supply circuit includes a power supply capacitor C provided separately from the output capacitor C and supplies a power supply voltage VCC to the protection circuit and an anode of the light emitting element of the photocoupler.

Abstract: A first capacitor and an auxiliary power supply are provided to a secondary side of an insulated synchronous rectification DC/DC converter, in addition to a synchronous rectification transistor and a secondary-side controller. One end of the first capacitor is connected to a first node that connects the synchronous rectification transistor and a secondary winding. The auxiliary power supply charges the first capacitor using the voltage VOUT supplied via the output line, so as to stabilize the voltage across the first capacitor. The ground voltage is supplied to the secondary-side controller via the first node. Furthermore, the power supply voltage is supplied to the secondary-side controller via the other end of the first capacitor.

Abstract: A rectifier IC seals, in a single package, a first transistor chip which integrates a first transistor, a second transistor chip which integrates a second transistor and a controller chip which detects a first node voltage and a second node voltage of each of the transistors so as to perform on/off control on the transistors, and the rectifier IC functions as a secondary-side rectification means of an isolated switching power supply.

Abstract: A secondary controller drives a light emitting element of a photocoupler such that a detection voltage VOUTS corresponding to an output voltage VOUT generated in an output capacitor C approximates to a reference voltage VREF. A primary controller controls a switching transistor M according to a feedback signal VFB. A protection circuit is activated and drives the light emitting element of the photocoupler when detecting an abnormal state. An auxiliary power supply circuit includes a power supply capacitor C provided separately from the output capacitor C and supplies a power supply voltage VCC to the protection circuit and an anode of the light emitting element of the photocoupler.

Abstract: In a first state, a multiplexer selects a voltage at a first drain pin. In a second state, the multiplexer selects a voltage at a second drain pin. A pulse generator generates a pulse signal SP based on an output voltage VD of the multiplexer. In the first state, the driving circuit switches on and off a first synchronous rectification transistor according to the pulse signal SP. In the second state, the driving circuit switches on and off a second synchronous rectification transistor according to the pulse signal SP. A phase controller switches the state between the first state and the second state.

Abstract: An insulated synchronous rectification DC/DC converter is provided. A feedback circuit drives a light-emitting element of a first photocoupler such that the output voltage VOUT of the DC/DC converter approaches a target voltage. A primary side controller is coupled to a light-receiving element of the first photocoupler, so as to switch on and off a switching transistor according to a feedback signal VFB. A synchronous rectification controller controls a synchronous rectification transistor. Upon detecting the occurrence of a switching-incapable state in the synchronous rectification transistor, a protection circuit instructs the primary side controller to stop the switching operation of the switching transistor.

Abstract: An isolated DC/DC converter includes a transformer having a first winding and a secondary winding, a switching transistor connected to the primary winding of the transformer, a rectifier element connected to the secondary winding of the transformer, a photocoupler, a feedback circuit configured to drive a light emitting element on an input side of the photocoupler by a forward current corresponding to an error between an output voltage of the DC/DC converter and a target voltage of the DC/DC converter, a conversion circuit configured to convert a collector current flowing in a light receiving element on an output side of the photocoupler into a feedback voltage having a negative correlation with the collector current, a pulse signal generator configured to generate a pulse signal corresponding to the feedback voltage, and a driver configured to drive the switching transistor depending on the pulse signal.

Abstract: The feedback IC is provided at the secondary side of the DC/DC converter and is coupled to the photo coupler. The error amplifier amplifies an error between a voltage detection signal according to an output voltage of the DC/DC converter and a target voltage, and draws a current according to the error from the input side of the feedback photo coupler via the photo coupler connection terminal. The abnormal detection circuit asserts an abnormal detection signal when an abnormal condition in a secondary side of the DC/DC converter is detected. The protection circuit is coupled to the photo coupler connection terminal, and acts on the feedback photo coupler via the photo coupler connection terminal so that a feedback operation by the error amplifier is invalid and an on-period of the switching transistor is shorten.

Abstract: A synchronous rectifier controller is provided on a secondary side of an insulation-type synchronous DC/DC converter and controls the synchronous rectifier transistor. A driver circuit controls the synchronous rectifier transistor. A photo coupler connection terminal is coupled to an input side of the photo coupler. An error amplifier amplifies an error between a voltage detection signal according to an output voltage of the DC/DC converter and its target voltage, and to draw a current according to the error from an input side of the photo coupler via the photo coupler connection terminal.

Abstract: The synchronous rectifier controller is provided at the secondary side of the insulation-type synchronous DC/DC converter and controls the synchronous rectifier transistor. The controller is coupled to the output of the feedback photo coupler and drives the switching transistor according to the feedback signal. The synchronous rectifier controller includes a driver circuit and an abnormal detection circuit and is configured as a single module. The driver circuit drives the synchronous rectifier transistor. The abnormal detection circuit detects an abnormal condition in the secondary side of the DC/DC converter. FAIL terminal is coupled to notify outside of an occurrence of the abnormal condition.