Abstract: A control circuit and control method for an interleaved switching converter having a first and second interleaved voltage regulating circuit. The control method is: controlling a first switch of the first voltage regulating circuit operating in quasi-resonant mode, turning ON a second switch of the second voltage regulating circuit after the first switch is turned ON for a half switching period, generating a current sensing signal by detecting a current flowing through the second switch, generating a peak signal, wherein the peak signal is adjusted when a voltage across the second switch is higher than a voltage reference at the time the second switch is turned ON, and turning OFF the second switch when the current sensing signal increases to the peak signal.

Abstract: A multi-converter switching power supply includes a first switching converter with a first output capacitor, a second switching converter with a second output capacitor, a bypass switch coupled across the second output capacitor, and a bypass control circuit for controlling the bypass switch. Input terminals of the first and switching converters are coupled in parallel, while output terminals of the first and switching converters are coupled in series to provide a total output voltage to a load. When detecting that the second output voltage approaches a negative voltage, the bypass control circuit turns on the bypass switch, so as to protect the second output capacitor from being damaged by a reverse DC voltage.

Abstract: A control method for controlling a battery charging circuit having at least one switch, includes: generating a first difference signal based on the difference between a charging current feedback signal and a charging current reference signal; generating a bias reference signal by proportionally integrating the first difference signal when the battery voltage is higher than a first threshold and less than a second threshold; generating a bias signal by proportionally integrating the difference between the sum of the bias reference signal and a system voltage reference signal and a system voltage feedback signal; generating a comparison signal by comparing the sum of the system voltage feedback signal and a ramp signal with the sum of the bias signal and the system voltage reference signal; and generating a control signal for controlling the at least one switch based on the comparison signal and a constant time period control signal.

Abstract: A method for automatically testing a voltage regulator, including: providing an auto-test setting to a test master, wherein the auto-test setting specifies an auto-sweep setting and a loop comprising an ordered set of serial command frames; producing, in the test master, a test suite comprising a plurality of serial command frames by executing the loop multiple times according to the auto-sweep setting until an array of a preset variable corresponding to the auto-sweep setting is traversed, wherein the preset variable is changed in each iteration of the loop; sequentially transmitting every serial command frame to the voltage regulator; and receiving every resulting behavior of the voltage regulator when operated in accordance with the every serial command frame.

Abstract: A control method used in a resonant converter with a switching circuit and a resonant circuit, wherein the switching circuit has a high side transistor coupled between an input voltage and a switch node and a low side transistor coupled between the switch node and a reference ground, the resonant circuit is coupled to the switch node and has a resonant capacitor and a resonant inductor. The method includes: generating an output feedback signal based on a signal of the resonant converter; sensing the voltage across the resonant capacitor generating a signal; comparing the output feedback signal with the voltage sensing signal to generate a high side off signal; determining when to turn off the high side transistor and turn on the low side transistor; detecting an on-time of the high side transistor; and determining when to turn off the low side transistor and turn on the high side transistor.

Abstract: A resonant converter includes: a rectifier bridge; a first capacitor coupled across output terminals of the rectifier bridge; a diode with its anode coupled to a first terminal of the first capacitor; a second capacitor with a first terminal coupled to the cathode of the diode, and a second terminal coupled to a second terminal of the first capacitor; a first transistor having a first terminal coupled to the first terminal of the second capacitor; a second transistor having a first terminal coupled to a second terminal of the first transistor, and a second terminal coupled to the second terminal of the first capacitor; a resonant tank having a first input terminal coupled to the first terminal of the first capacitor, and a second input terminal coupled to the second terminal of the first transistor and the first terminal of the second transistor; and a rectifying and filtering circuit coupled across output terminals of the resonant tank, and configured to provide an output signal to a load.

Abstract: A semiconductor device for limiting inrush current in hot-swap applications includes a power transistor and a current sensing circuit. The power transistor has a first terminal, a second terminal and a control terminal, wherein the first terminal is configured to receive an input voltage from a power supply, the second terminal is configured to provide an output voltage to a load, the control terminal is configured to receive a control voltage. Under regulation of the control voltage, the output voltage increases gradually towards the input voltage during a startup period and becomes substantially equal to the input voltage in a steady state. The current sensing circuit senses the current flowing through the power transistor and generates a current sensing signal. In order to achieve current balance, the control voltage is adjusted based on the relationship between the current sensing signal and current sensing signals of other semiconductor devices connected in parallel with the semiconductor device.

Abstract: A battery fuel gauge current sensing circuit includes: a sense unit coupled in series with the battery and configured to sense the battery current; a control unit configured to adjust the ON resistance of the sense unit based on the comparison of the voltage across the sense unit and a threshold voltage until the voltage across the sense unit is greater than the threshold voltage; and a sample unit coupled across the sense unit and configured to sample the voltage across the sense unit and to provide an analog sample voltage when the voltage across the sense unit is greater than the threshold voltage.

Abstract: A method of capacitive mode detection is used in a resonant converter. The resonant converter has a square wave generator having a first switch and a second switch, a resonant network, an isolated transformer having a primary winding and a second winding, and a rectifier network providing an output DC voltage for a load. The method of capacitive mode detection includes: detecting a voltage of the secondary winding and generating a voltage detection signal; detecting an output DC voltage of the rectifier network and generating a voltage detecting threshold; comparing the voltage detection signal with the voltage detection threshold when either of the first and the second switches is turned OFF; generating a flag signal indicating whether the resonant converter enters into a capacitive mode based on the comparison result.

Abstract: A primary control LED driver includes: a switching converter having a main switch and a first winding, and configured to provide an LED driving current; a second winding magnetically coupled to the first winding and configured to provide a power supply voltage at a first terminal; a first sensing resistor with a first terminal coupled to the main switch; a second sensing resistor with a first terminal coupled to the second terminals of the first sensing resistor and the second winding; an output current calculator calculating an equivalent value of the LED driving current based on the voltage at the first terminal of the first sensing resistor; an error amplifier configured to generate a compensation signal based on the equivalent value and a reference voltage; and a control circuit generating a control signal to control the main switch based on the compensation signal.