Chengdu Monolithic Power Systems Co., Ltd.

Monolithic Power Systems, Inc.

Zhijiang Yang

Yuancheng Ren

Bo Yu

Naixing Kuang

Lei Du

Jian Zhang

A driving circuit for a power transistor. The driving circuit has a control pin to receive a control signal, a driving pin to provide a driving signal to control the power transistor, the driving signal is generated based on the control signal. The driving circuit also has a negative voltage isolation circuit connected between an isolation pin and an output pin, when the voltage at the output pin is greater than an isolation voltage, the voltage at the isolation pin is equal to the voltage at the output pin, and when the voltage at the output pin is less than the isolation voltage, the voltage at the isolation pin is clamped at a preset voltage value, the preset voltage value is in a range from −2V to −0.2V.

Driving circuit having a negative voltage isolation circuit

A current generating circuit generating a current relevant to a reference voltage. The current generating circuit has a reference clock generating circuit generating a reference clock signal which has a frequency relevant to the reference voltage. The current generating circuit has a phase locked loop circuit generating a calibration clock signal. The phase clocked loop circuit regulates the calibration clock signal so that the phase difference between the calibration clock signal and the reference clock signal is reduced. The current generating circuit has also an output circuit generating an output current according to the phase difference between the calibration clock signal and the reference clock signal.

Current generating circuit generating a current relevant to a reference voltage

A signal amplifying system having an oscillator and an amplifying circuit. The oscillator has a first resistor with a first resistance Rand a first capacitor with a first capacitance C, and generates an oscillating signal having a frequency f which equals to k1/(R*C), k1 is a first proportional parameter. The amplifying circuit has an input terminal to receive an input signal and amplifies the input signal under the control of the oscillating signal. The amplifying circuit has a second resistor with a second resistance Rand a second capacitor with a second capacitance C. The amplifying circuit has a &#x2212;3 dB bandwidth Wwhich equals to k2/(R*C), k2 is a second proportional parameter. In this signal amplifying system, the product of the first resistance Rand the first capacitance Cis proportional to the product of the second resistance Rand the second capacitance C

Signal amplifying system in a hall detecting and amplifying system

A LED driver system includes a LED converter converting an input voltage to an output voltage to drive a LED load via a main switch; a sensing circuit generating a feedback signal on the output terminal according to a load current through the LED load; an over-shoot detecting circuit generating an over-shoot signal according to the load current and a second reference signal; a logic circuit generating a switching signal according to a control signal and the over-shoot signal to control the main switch. The control signal is generated according to the feedback signal and a first reference signal, and the second reference signal is larger than the first reference signal.

LED driver system, controller and associated method

A LED driving control circuit for controlling a power switch in a LED power supply includes: a feedback circuit coupled to a LED load and generating a feedback signal indicative of an output voltage of the LED power supply; an enabling circuit generating an enable signal according to the feedback signal, a first reference signal and a PWM dimming signal, wherein when the feedback signal is higher than the first reference signal, the enable signal synchronizes with the PWM dimming signal, and when the feedback signal is lower than the first reference signal, the duty cycle of the enable signal is higher than the duty cycle of the PWM dimming signal; and a feedback loop control circuit generating a control signal for controlling the power switch according to the feedback signal only when the enable signal is in an active state.

LED power supply with small dimming ratio control and control method thereof

The present disclosure discloses a light emitting element driving circuit. In one embodiment the light emitting element driving circuit may comprise a power conversion circuit and a current balancing circuit. In other embodiment the light emitting element driving circuit may further comprise other modules integrated and interacting with the power conversion circuit and the current balancing circuit, such as fault detection and protection circuits, status indication circuits and phase-shift PWM dimming circuits. In other embodiment, the present disclosure further discloses a current balancing circuit. In other embodiment, the present disclosure further discloses a fault detection and protection circuit. In still other embodiment, the present disclosure further discloses a phase-shift PWM dimming circuit.

Light emitting element driving circuit

The present disclosure discloses a multi-mode dimming circuit configurable to operate in a first dimming mode, a second dimming mode and a third dimming mode. The present disclosure also discloses separate dimming circuits for respectively realize the three dimming modes. In one embodiment the multi-mode dimming circuit may comprise a first input terminal, a second input terminal, a third input terminal, an output terminal, a resistive device, an oscillation circuit and a pulse width modulation (PWM) circuit. Users may flexibly configure the multi-mode dimming circuit to operate in one of the three different dimming modes by varying the external devices and/or signals coupled to each of the first, second and third input terminals.

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Chengdu, China

Zhijiang Yang