Hangzhou Silan Microelectronics Co., Ltd.

Jianxing Wu

Yunlong Yao

Xianming Tang

Dong Wang

Shaohua Zhang

Yang Gao

Hua Zhan

Feng Yao

Haifeng Lin

Xianwei Yan

Xiaogao Xie

The disclosure relates to an error amplification apparatus and a driving circuit including the error amplification apparatus. In the error amplification apparatus according to the disclosure, a pulse generating circuit generates a first pulse and a second pulse in accordance with an output voltage of an error amplification unit, a counting unit being coupled to the pulse generating circuit counts the first pulse and the second pulse, and generates a loop control signal representing a compensation voltage based on the count. The disclosure utilizes the counting unit to digitize the compensation voltage, and the counter value can reflect the compensation voltage, so that the variation of the loop control signal in the AC cycle of 50 Hz or 60 Hz is controlled to be little, thereby filtering out the ripple of AC of 50 Hz or 60 Hz. In this manner, the capacitance of the compensation capacitor is reduced so that the compensation capacitor can be integrated inside the IC chip, thereby simplifying the peripheral design, and eliminating the influence on the loop by the electrical leakage current due to moisture.

Error amplification apparatus and driving circuit including the same

The present invention provides a switching power supply and a controller thereof, wherein the controller comprises: a switching power supply control device having a power supply terminal and detecting a voltage at the power supply terminal; a composite device integrating therein a power transistor and a depletion transistor, wherein the power transistor has a gate coupled to a first input, a source coupled to a first output, and a drain coupled to an input signal terminal; the depletion transistor has a gate coupled to a second input, a source coupled to a second output, and a drain coupled to the input signal terminal; the first input, the second input and the second output are coupled to the switching power supply control device, the first input receives a driving signal generated by the switching power supply control device, and the input signal terminal receives an input signal of the switching power supply. The power transistor and the depletion transistor in the composite device may be integrated within the same composite device. The present invention can shorten the startup time of the switching power supply, effectively reduce the standby power consumption, and also reduce the cost.

Switching power supply and the controller thereof

A switch-mode power supply control apparatus includes a PWM controller for outputting a driving signal and a short-circuit protection module coupled to a detection terminal. The detection terminal receives a zero-crossing detection voltage. If the time that the detection voltage input to the detection terminal is lower than a first reference voltage exceeds a predetermined time period, the short-circuit protection module determines that a short-circuit abnormal situation occurs, the short-circuit protection module outputs a short-circuit signal to the PWM controller, and the driving signal output by the PWM controller becomes a turn-off signal. If the short-circuit protection module does not detect the short-circuit abnormal situation, the PWM controller operates normally. A flyback switch-mode power supply includes the switch-mode power supply control apparatus. The flyback switch-mode power supply has a low power consumption when a short-circuit protection is taking place.

Switch-mode power supply control apparatus and flyback switch-mode power supply including the control apparatus

The present invention discloses a primary-side controlled switch-mode power supply controller for driving LED with constant current and method thereof as well as an apparatus for controlling switch-mode power supply having the switch-mode power supply controller. The switch-mode power supply controller includes an input dimming phase detection circuit, a multiplier, a turn-on signal control circuit, a zero-crossing detection circuit, a comparator, a trigger and a driving circuit. The circuit controls to drive LED with constant current by means of a primary-side controlled method. The circuit realizes the triac dimming function, ensures a constant output current regardless of a high voltage or a low voltage, and obtains a high power factor. The direct use of the isolation transformer improves the safety of the circuit, and simplifies the peripheral circuit, thereby reducing the cost of the circuit and minimizing the size of the PCB layout, which is favorable in minimizing the product.

Primary-side controlled switch-mode power supply controller for driving LED with constant current and method thereof

A current reference generating circuit including a first multiplier module, configured to receive a rectified voltage waveform signal of a switch mode power supply and an output signal generated by an average current loop, and to generate a sinusoidal half-wave signal having the same frequency and phase as the rectified voltage waveform signal, the sinusoidal half-wave signal varies with the output signal generated by the average current loop. A second multiplier module, configured to receive the sinusoidal half-wave signal and a control signal to generate a pulse signal. An average current loop for comparing the average of the pulse signal to a predetermined average current loop reference signal. The circuit can generate a self-adapted reference signal that follows the primary-side current signal of main circuit of the switch mode power supply, which is then supplied to the constant current switch mode power supply control circuit with high power factor.

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Hangzhou, China

Jianxing Wu