Abstract: A switching converter includes a main transistor, an inductor coupled to the main transistor, a feedback circuit configured to generate a feedback signal indicative of the output voltage and a controller configured to generate a control signal to control the main transistor. The controller has an on timer, a ramp generator, a comparing circuit and a logic circuit. The on timer is configured to generate an on-time control signal. The ramp generator is configured to generate a ramp signal, wherein the level of the ramp signal is regulated to be equal to the level of a common mode voltage when the status of the main transistor is changed from OFF to ON. The comparing circuit generates a comparison signal based on the ramp signal, the common mode voltage, a reference signal and the feedback signal. The logic circuit generates the control signal based on the on-time control signal and the comparison signal.

Abstract: A short protection circuit for protecting a power switch. The short protection circuit has a transistor and compares a differential voltage between a first end of the power switch and a second end of the power switch to a threshold voltage of the transistor only when the power switch is in an ON state; and wherein when the differential voltage is higher than the threshold voltage, the short protection circuit turns off the power switch.

Abstract: A current detection circuit for detecting a current in a SMPS which has a first switch and a second switch; a current sensing circuit sensing a second switch current flowing through the second switch and providing a current sensing signal; and a current emulation circuit which generates a first current according to the current sensing signal and generate a second current according to the first current source, and the current emulation circuit further providing a current emulation signal based on the first current source and the second current source; wherein a current detection signal during a first period is proportional to the current emulation signal, and the current detection signal during a second period is proportional to the current sensing signal.

Abstract: A current detection circuit for detecting a current in a SMPS which has a first switch and a second switch; a current sensing circuit sensing a second switch current flowing through the second switch and providing a current sensing signal; and a current emulation circuit which generates a first current according to the current sensing signal and generate a second current according to the first current source, and the current emulation circuit further providing a current emulation signal based on the first current source and the second current source; wherein a current detection signal during a first period is proportional to the current emulation signal, and the current detection signal during a second period is proportional to the current sensing signal.

Abstract: A short protection circuit for protecting a power switch. The short protection circuit has a transistor and compares a differential voltage between a first end of the power switch and a second end of the power switch to a threshold voltage of the transistor only when the power switch is in an ON state; and wherein when the differential voltage is higher than the threshold voltage, the short protection circuit turns off the power switch.

Abstract: A switch-mode voltage converter has a switching transistor coupled between an input voltage (Vin) and the ground and a controller coupled directly between the input voltage (Vin) and the ground. The controller periodically turns on the switching transistor for a generally constant period of time. The controller is further coupled to a DC bias voltage (Vbias) and generates a control current based on the input voltage (Vin) and the DC bias voltage (Vbias) for generating a switching signal to the switching transistor.

Abstract: A security system and method which includes a main automatically acting circuit 10 and portions which may be manually activated by a user to provide better deterrence to a home invader or burglar (11-14). The manually activated portions turn on an audible alarm and/or lights which may or may not be in the automatic section. Thus, economy of manufacture with enhanced safety and security is achieved. A variable alarm system is thus presented to a potential intruder to more effectively terminate a possible home invasion or robbery. The method includes remote control devices and remote detection devices so a user can remotely stop a home invasion or burglary.

Abstract: Switch-mode voltage converters and associated methods are disclosed herein. In one embodiment, a switch-mode voltage converter includes a switching transistor coupled between an input voltage (Vin) and the ground and a controller coupled directly between the input voltage (Vin) and the ground. The controller is configured to periodically turn on the switching transistor for a generally constant period of time. The controller is further coupled to a DC bias voltage (Vbias) and configured to generate a control current based on the input voltage (Vin) and the DC bias voltage (Vbias) for generating a switching signal to the switching transistor.

Abstract: A circuit is disclosed that includes a buck voltage regulator electrically coupled to an active current modulator. The active current modulator is operable to detect a negative current in the low-side switch of the buck voltage regulator circuit during a light mode operation. Whenever the negative current is detected, the active negative current modulator causes the low-side switch to stay ON in a linear mode and limits the negative current to a predetermined current level.

Abstract: For a DC to DC converter circuit integrated on a packaged die, the relative positions of various die pads and power MOSFETs on the die for a small outline integrated circuit package are described.

Abstract: A circuit is disclosed that includes a buck voltage regulator electrically coupled to an active current modulator. The active current modulator is operable to detect a negative current in the low-side switch of the buck voltage regulator circuit during a light mode operation. Whenever the negative current is detected, the active negative current modulator causes the low-side switch to stay ON in a linear mode and limits the negative current to a predetermined current level.

Abstract: A circuit is disclosed that includes a buck voltage regulator electrically coupled to an active current modulator. The active current modulator is operable to detect a negative current in the low-side switch of the buck voltage regulator circuit during a light mode operation. Whenever the negative current is detected, the active negative current modulator causes the low-side switch to stay ON in a linear mode and limits the negative current to a predetermined current level.

Abstract: A switch-mode synchronous boost voltage regulator is disclosed that includes a boost voltage regulator and an active current modulator. The active current modulator detects a negative current flowing through the high-side switch during a light load condition. When the negative current is detected, the active current modulator is operable to maintain the high-side switch “on” in a linear mode and to limit the negative current to a predetermined current level.

Abstract: For a DC to DC converter circuit integrated on a packaged die, the relative positions of various die pads and power MOSFETs on the die for a small outline integrated circuit package are described.

Abstract: A switch-mode synchronous boost voltage regulator is disclosed that includes a boost voltage regulator and an active current modulator. The active current modulator detects a negative current flowing through the high-side switch during a light load condition. When the negative current is detected, the active current modulator is operable to maintain the high-side switch “on” in a linear mode and to limit the negative current to a predetermined current level.

Abstract: A circuit is disclosed that includes a buck voltage regulator electrically coupled to an active current modulator. The active current modulator is operable to detect a negative current in the low-side switch of the buck voltage regulator circuit during a light mode operation. Whenever the negative current is detected, the active negative current modulator causes the low-side switch to stay ON in a linear mode and limits the negative current to a predetermined current level.

Abstract: Methods and apparatus are disclosed for controlling switching regulators to automatically switch from a traditional pulse-width modulation (PWM) mode, when the load current is higher than a predetermined value, to a pulse-frequency modulation (PFM) mode, when the load current drops to a point lower than the predetermine value. Switching modes increases the efficiency of the regulator when the load current is low without provoking a large output voltage transient. In some embodiments, a single switching cycle regulates the output in the PFM mode, which reduces the switching losses and enhances the efficiency of the regulator.

Abstract: The present invention introduces methods and circuits to provide a soft start for a switching regulator. A feedback voltage from output terminal is monitored and used to regulate the bias current of the regulator's error amplifier. The present invention also enables a smooth transition from the soft start to normal operation.

Abstract: Methods and apparatus are disclosed for controlling switching regulators to automatically switch from a traditional pulse-width modulation (PWM) mode, when the load current is higher than a predetermined value, to a pulse-frequency modulation (PFM) mode, when the load current drops to a point lower than the predetermine value. Switching modes increases the efficiency of the regulator when the load current is low without provoking a large output voltage transient. In some embodiments, a single switching cycle regulates the output in the PFM mode, which reduces the switching losses and enhances the efficiency of the regulator.

Abstract: A commutation control circuit for a conventional brushless DC motor. The circuit reduces power supply noise normally induced when current is switched from one pair of motor windings to the next. The motor conventionally includes a number of windings, each of which includes a terminal connected to a common center tap. The commutation circuit includes a first voltage-controlled current switch that is connected to the second terminal of a first one of the windings to control current through the first winding. Similarly, the second terminal of a second on of the windings is connected to a second voltage-controlled current switch. When a commutation is initiated to switch the current flow from the first to the second winding, the commutation circuit turns the second voltage-controlled switch fully on to quickly increase the current level through the second winding.