Patent application number | Description | Published |
20090128973 | Power supply control circuit including overvoltage protection circuit - A protection ability of a power supply control circuit is improved so as to protect an output transistor against a back electromotive voltage from a load, a dump surge voltage, and a positive spike surge voltage which has a smaller energy but is higher than the dump surge voltage. The power supply control circuit includes: an output MOS transistor (power semiconductor device) connected between a first power supply terminal and an output terminal; a load connected to the output terminal; a first dynamic clamping circuit for controlling a voltage difference between a first power supply line and the output terminal; and a first switch connected between the first dynamic clamping circuit and the output MOS transistor, in which a conductive state is determined according to a result of comparison between a reference voltage and a voltage at the output terminal. The power supply control circuit further includes a second dynamic clamping circuit for controlling a voltage difference between the first power supply terminal and the output terminal to protect the output MOS transistor. The second dynamic clamping circuit operates in response to application of a positive spike surge voltage which is higher than the dump surge voltage. | 05-21-2009 |
20090146628 | POWER SUPPLY CONTROL CIRCUIT - An exemplary aspect of a power supply control circuit includes a reference voltage control circuit that applies a potential corresponding to a potential of a second power supply line to a reference voltage node connected to a control terminal of a first switch when a power supply voltage is applied in a forward direction between first and second power supply lines, and that applies a potential corresponding to a potential of a first power supply line to the reference voltage node when the power supply voltage is applied in the reverse direction between the first and second power supply lines. | 06-11-2009 |
20090147422 | POWER SUPPLY CONTROL CIRCUIT - A power supply control circuit includes a control circuit that controls an output transistor to be rendered conductive by forming a second electrical path between a second power supply line and a control terminal of the output transistor when a power supply voltage is applied in a reverse direction between first and second power supply lines, and that controls a second electrical path to be electrically disconnected when the power supply voltage is applied in a forward direction between the first and second power supply lines. | 06-11-2009 |
20090153225 | Load Driving Device - A load driving device according to an aspect of the invention may includes an output transistor connected between a power supply line and an output terminal, a load connected between the output terminal and a first ground line, a control circuit connected between a gate of the output transistor and a second ground line, the control circuit controlling turning on/off of the output transistor, and a compensation transistor that turns on when a potential of the second ground line assumes a predetermined value or higher, thereby maintaining an off state of the output transistor. | 06-18-2009 |
20090154041 | Load driving device - A load driving device according to an aspect of the present invention may includes an output transistor and a load connected in series between first and second power supply lines, a protection transistor connected between a gate of the output transistor and the second power supply line, the protection transistor turning on the output transistor when a polarity of a power supply connected between the first and second power supply lines is reversed, and a resistor arranged on a line, which supplies a voltage to a back gate of the protection transistor. | 06-18-2009 |
20090160498 | Semiconductor output circuit for controlling power supply to a load - Between a control terminal (gate) of an output transistor of a source follower configuration and an output terminal to which a load is coupled, a depletion transistor having a relatively lower breakdown voltage (that is, smaller device-area) is provided as a shutdown transistor of the output transistor, to thereby control a conductive state/nonconductive state of the depletion transistor. There are provided: the output transistor of the source follower configuration coupled between a first power supply line and the output terminal; the load coupled between the output terminal and a second power supply line; the depletion transistor coupled between the gate of the output transistor and the output terminal; and a control circuit controlling the conductive state/nonconductive state of the depletion transistor by applying, between a gate and a source thereof, a voltage smaller than a voltage deference between a potential of the first power supply line and a potential of the second power supply line. | 06-25-2009 |
20090160499 | Semiconductor output circuit - To improve a depletion transistor provided between a control terminal of an output transistor and an output terminal coupled to a load not to enter a conductive state when the output transistor is in the conductive state. The output transistor is served as a source follower. Control voltages which controlling the conductive state/nonconductive state of the depletion transistor are supplied to both a control terminal (gate) and a substrate terminal (back gate) of the depletion transistor. | 06-25-2009 |
20100134941 | Semiconductor device including over voltage protection circuit having gate discharge circuit operated based on temperature and voltage as to output transistor - A semiconductor device includes an output transistor which controls a power supply to a load according to a control voltage applied to a gate thereof, a voltage control circuit coupled between the gate and a drain of the output transistor, the voltage control circuit having a conduction state controlled according to a potential difference between a source and the drain of the output transistor, and a voltage control detection circuit which outputs a voltage control detection signal on a basis of the conduction state of the voltage control circuit. A first discharge switch is connected between the gate and the source of the output transistor, an on-off state of the first discharge switch being controlled according to the voltage control detection signal, a second discharge switch is series-connected to the first discharge switch between the gate and the source of the output transistor, an on-off state of the second discharge switch being controlled according to a temperature condition of the output transistor, and a third discharge switch is connected in parallel with the first and second discharge switches. | 06-03-2010 |
20100207605 | Power supply control apparatus including overcurrent detection circuit - Provided is a power supply control apparatus including an overcurrent detection circuit with enhanced overcurrent detection accuracy. A power supply control apparatus according to the present invention includes: an output transistor Q | 08-19-2010 |
20100207665 | Comparator circuit - A comparator circuit, includes first and second terminals to which a reference voltage that determines a threshold voltage is inputted, a third terminal to which a standard voltage is inputted, a fourth terminal to which a target voltage that is to be detected and is based on the standard voltage is inputted, first and second transistors of a first conductivity type including control terminals connected to the first and second terminals, respectively, the first and second transistors flowing currents depending on a potential difference of the reference voltage, a third transistor of a second conductivity type connected in series with the first transistor, a fourth transistor of the second conductivity type connected in series with the second transistor, a fifth transistor of the second conductivity type through which a mirror current depending on a current flowing through the third transistor, a sixth transistor of the second conductivity type flowing a mirror current depending on a current flowing through the fourth transistor, a seventh transistor of the first conductivity type connected between the sixth transistor and the fourth terminal, and an eighth transistor of the first conductivity type connected between the fifth transistor and the third terminal, the eighth transistor flowing a mirror current depending on a current passing through the seventh transistor. A voltage depending on a voltage of an intermediate node between the fifth and eighth transistors is outputted as an output signal. | 08-19-2010 |
20100207666 | Comparator circuit - A comparator circuit, includes first and second terminals to which a reference voltage that determines a threshold voltage is inputted, a third terminal to which a standard voltage is inputted, a fourth terminal to which a target voltage that is to be detected and is based on the standard voltage is inputted, first and second transistors of a first conductivity type including control terminals to the first and second terminals, respectively, the first and second transistors flowing currents depending on a potential difference of the reference voltage, a third transistor of a second conductivity type connected between the first transistor and the fourth terminal, and a fourth transistor of the second conductivity type connected between the second transistor and the third terminal, the fourth transistor flowing a mirror current depending on a current passing through the third transistor. A voltage depending on a voltage of an intermediate node between the second and fourth transistors is outputted as an output signal. | 08-19-2010 |
20100208404 | Power supply control apparatus including overcurrent detection circuit - Provided is a power supply control apparatus including an overcurrent detection circuit having an overcurrent detection accuracy improved. The power supply control apparatus according to the present invention includes: a transistor Q | 08-19-2010 |
20110101935 | POWER SUPPLY CONTROL APPARATUS - A power supply control apparatus includes: an output transistor coupled between a first power supply line and an output terminal, the output terminal being configured to be coupled with a load; a protection transistor coupled between a gate of the output transistor and a second power supply line; a negative voltage control unit coupled between the first power supply line and the gate of the output transistor; a compensation transistor bringing the second power supply line and the output terminal into a conduction state when a counter electromotive voltage from the load is applied to the output terminal; and a back gate control circuit that controls the second power supply line and a back gate of each of the compensation transistor and the protection transistor to be brought into a conduction state in a standby state when the polarity of the power supply is normal. | 05-05-2011 |
20110101941 | LOAD DRIVING DEVICE - A load driving device according to an exemplary aspect of the present invention includes: an output transistor coupled between a first power supply line and an output terminal; the output terminal being configured to be coupled with a load; a driver circuit that controls conduction/non-conduction of the output transistor; a compensation transistor that is coupled between the output terminal and a second power supply line, and becomes conductive when the driver circuit renders the output transistor non-conductive and when a potential of the second power supply line reaches a predetermined value or greater, to maintain a non-conduction state of the output transistor; and a first resistor coupled between the second power supply line and a back gate of the compensation transistor. | 05-05-2011 |
20110102956 | LOAD DRIVING DEVICE - A load driving device according to an exemplary aspect of the present invention includes: an output transistor coupled between a first power supply line and an output terminal, the output terminal being configured to be coupled with a load; a protection transistor that is provided between a gate of the output transistor and a second power supply line, and brings the output transistor into a conduction state when a polarity of a power supply coupled between the first power supply line and the second power supply line is reversed; and a back gate control circuit that controls the second power supply line and a back gate of the protection transistor to be brought into a conduction state in a standby mode when the polarity of the power supply is normal. | 05-05-2011 |
20110163794 | POWER SUPPLY CONTROL CIRCUIT - A power supply control circuit comprises an output transistor which controls supply of electric power to a load and a gate driving circuit which generates control signals “a” and “b” for controlling on/off of the output transistor | 07-07-2011 |
20110163800 | POWER SUPPLY CONTROL CIRCUIT - A power supply control circuit comprises an output transistor | 07-07-2011 |
20110193541 | CURRENT LIMITING CIRCUIT - An exemplary aspect of the present invention is a current limiting circuit including: an output transistor that controls a current flowing to a load from a power supply; a current sense transistor through which a current dependent on a current flowing through the output transistor flows; a sense resistor connected in series with the current sense transistor; a potential difference detection unit that detects a potential difference generated between both ends of the sense resistor; a constant current generation unit that supplies a constant current to the potential difference detection unit; and a control unit that controls a conduction state of the output transistor based on a control voltage generated based on the potential difference and the constant current, in which the sense resistor is disposed so as to surround the potential difference detection unit. | 08-11-2011 |
20110279152 | LOAD DRIVING DEVICE - Malfunction attributable to an induced electromotive force such as a back electromotive force or a regenerative braking force of an inductive load in a load driving device is prevented. When an on-state current flows in an output transistor, a second transistor applies a supply voltage applied to a source of the output transistor to a back gate of the first transistor. On the other hand, when a negative current flows in the output transistor in a direction opposite to that of the on-state current, the second transistor applies a supply voltage applied to a drain of the output transistor to the back gate of the first transistor. | 11-17-2011 |
20120032707 | Load driving device - A load driving device includes a power supply terminal, a ground terminal, an output terminal coupled to a load, an output transistor coupled between the power supply and output terminals, a driver circuit supplying a first control signal to turn on the output transistor and a second control signal to turn off the output transistor, a discharge circuit coupled between the control terminal of the output transistor and the output terminal, a compensation circuit that turns on when a potential of the ground terminal is at least a predetermined value to maintain a non-conductive state of the output transistor when a polarity of a power supply coupled between the power supply and ground terminals is normal, and a reverse connection protection circuit coupled between the control terminal and the ground terminal, which brings the output transistor into a conductive state when a polarity of the power supply is reversed. | 02-09-2012 |
20120098587 | Power semiconductor device and operation method thereof - A power semiconductor device has: an output transistor connected between a power-supply terminal and an output terminal; a gate charge-discharge circuit configured to charge/discharge a first node connected to a gate of the output transistor to ON/OFF control the output transistor; a short switch circuit connected between the first node and the output terminal; and a short control circuit configured to control the short switch circuit. In the turn-ON period, the ON period and the turn-OFF period, the short control circuit cuts off electrical connection between the first node and the output terminal through the short switch circuit. In the OFF period, the short control circuit electrically connects the first node and the output terminal through the short switch circuit. | 04-26-2012 |
20120188674 | LOAD DRIVING DEVICE - A load driving device according to an aspect of the present invention may includes an output transistor and a load connected in series between first and second power supply lines, a protection transistor connected between a gate of the output transistor and the second power supply line, the protection transistor turning on the output transistor when a polarity of a power supply connected between the first and second power supply lines is reversed, and a resistor arranged on a line, which supplies a voltage to a back gate of the protection transistor. | 07-26-2012 |
20130278236 | CURRENT LIMITING CIRCUIT - An exemplary aspect of the present invention is a current limiting circuit including: an output transistor that controls a current flowing to a load from a power supply; a current sense transistor through which a current dependent on a current flowing through the output transistor flows; a sense resistor connected in series with the current sense transistor; a potential difference detection unit that detects a potential difference generated between both ends of the sense resistor; a constant current generation unit that supplies a constant current to the potential difference detection unit; and a control unit that controls a conduction state of the output transistor based on a control voltage generated based on the potential difference and the constant current, in which the sense resistor is disposed so as to surround the potential difference detection unit. | 10-24-2013 |
20140022001 | POWER SEMICONDUCTOR DEVICE - A power semiconductor device includes an output transistor, a control circuit connected with a gate of the output transistor, a first discharge route from a first node to a ground terminal, and a second discharge route from the first node to the ground terminal. In a usual turn-off, only the first discharge route is used. When a load abnormality occurs, both of the first and second discharge routes are used. The second discharge route contains a discharge transistor and a countercurrent prevention device. The discharge transistor is connected between the first node and the second node. The countercurrent prevention device prevents a flow of current from the third node to the second node. At least, in an OFF period, the control circuit sets the gate voltage of the discharge transistor to a high level. | 01-23-2014 |
20150022247 | POWER SEMICONDUCTOR DEVICE - A power semiconductor device includes an output transistor, a control circuit connected with a gate of the output transistor, a first discharge route from a first node to a ground terminal, and a second discharge route from the first node to the ground terminal. In a usual turn-off, only the first discharge route is used. When a load abnormality occurs, both of the first and second discharge routes are used. The second discharge route contains a discharge transistor and a countercurrent prevention device. The discharge transistor is connected between the first node and the second node. The countercurrent prevention device prevents a flow of current from the third node to the second node. At least, in an OFF period, the control circuit sets the gate voltage of the discharge transistor to a high level. | 01-22-2015 |