Abstract: A drive circuit with a zero-crossing detection function, and a zero-crossing detection method. The drive circuit comprises: a power switch transistor, a pull-up drive transistor, a first pull-down drive transistor and a second pull-down drive transistor. When an inductor starts to discharge, the first pull-down current and the second pull-down current jointly pull down a gate terminal of the power switch transistor, such that the power switch transistor is in a cut-off state; after a set time, the first pull-down current is turned off; and when the inductor ends discharging, a parasitic capacitance of the power switch transistor couples with the drop signal, and when the drop signal is detected, the pull-up current pulls up the gate terminal of the power switch transistor, such that the power switch transistor is in a turn-on state.

Abstract: A LED driving circuit and method for balancing efficiency and a power factor. The circuit comprises a voltage input module, an LED load, a constant current control module and a current turn-off slope control module for adjusting the turn-off slope of the current flowing through the LED load, such that a compromise between efficiency and power factor is achieved. When an input voltage is higher than a setting voltage, the current flowing through the LED load is turned off, such that the power consumption is reduced; in addition, the efficiency and power factor are balanced by adjusting the turn-off slope of the current. According to the present invention, a compensation capacitor is used to control the average current in an alternating current period and to limit peak current, thereby implementing constant power output within a wide range of input voltage.

Abstract: A LED driving circuit and method for balancing efficiency and a power factor. The circuit comprises a voltage input module, an LED load, a constant current control module and a current turn-off slope control module for adjusting the turn-off slope of the current flowing through the LED load, such that a compromise between efficiency and power factor is achieved. When an input voltage is higher than a setting voltage, the current flowing through the LED load is turned off, such that the power consumption is reduced; in addition, the efficiency and power factor are balanced by adjusting the turn-off slope of the current. According to the present invention, a compensation capacitor is used to control the average current in an alternating current period and to limit peak current, thereby implementing constant power output within a wide range of input voltage.

Abstract: A single-segment linear constant-power LED driving circuit and method. The circuit comprises: a voltage input module, an LED load, a power switch tube, a sampling resistor, an over-voltage control module for detecting the voltage at a drain terminal of the power switch tube, a current control module for limiting a peak current of the LED load, and a comparison module. When an input voltage is greater than a turn-on voltage of the LED load, the current control module limits the peak current so that the current average value in different input voltage periods is constant. When the input voltage is greater than a set value, current flowing through the LED load is turned off, thereby reducing power consumption. When the input voltage is less than the turn-on voltage of the LED load, the LED load is turned off.

Abstract: A system and method for detecting voltage of a battery pack. The system comprises a level transfer circuit array, a multipath data selector, a decoder, a trimming calibration circuit, and an output buffer. The decoder is configured to parse a battery pack cell gating signal; the level transfer circuit array is configured to convert a gated battery pack cell voltage into a common grounded voltage; the multipath data selector is configured to transmit the common grounded voltage, which is converted by the level transfer circuit array, of a battery pack cell to the trimming calibration circuit; the trimming calibration circuit is configured to correct the received common grounded voltage of the battery pack cell; and the output buffer is configured to buffer the common grounded voltage, which is trimmed and calibrated by the trimming calibration circuit, of the battery pack cell.

Abstract: A single-segment linear constant-power LED driving circuit and method. The circuit comprises: a voltage input module, an LED load, a power switch tube, a sampling resistor, an over-voltage control module for detecting the voltage at a drain terminal of the power switch tube, a current control module for limiting a peak current of the LED load, and a comparison module. When an input voltage is greater than a turn-on voltage of the LED load, the current control module limits the peak current so that the current average value in different input voltage periods is constant. When the input voltage is greater than a set value, current flowing through the LED load is turned off, thereby reducing power consumption. When the input voltage is less than the turn-on voltage of the LED load, the LED load is turned off.

Abstract: A system and method for detecting voltage of a battery pack. The system comprises a level transfer circuit array, a multipath data selector, a decoder, a trimming calibration circuit, and an output buffer. The decoder is configured to parse a battery pack cell gating signal; the level transfer circuit array is configured to convert a gated battery pack cell voltage into a common grounded voltage; the multipath data selector is configured to transmit the common grounded voltage, which is converted by the level transfer circuit array, of a battery pack cell to the trimming calibration circuit; the trimming calibration circuit is configured to correct the received common grounded voltage of the battery pack cell; and the output buffer is configured to buffer the common grounded voltage, which is trimmed and calibrated by the trimming calibration circuit, of the battery pack cell.