LED driver based on MP3302 LED driver IC. Working circuit diagram.Operates from a single Lithium ion battery

Posted on Feb 5, 2014

MP3302 is a boost converter IC specifically designed for LED drive applications. The MP3302 can drive 27 LEDs (9 strings of 3 white LEDs in series) from a Lithium ion battery. The IC has internal power MOSFETs for driving the LEDs and has an efficiency of 88%. Switching frequency is 1. 3MHz and the internal current limit is 1. 33A. Other features of

LED driver based on MP3302 LED driver IC. Working circuit diagram.Operates from a single Lithium ion battery
Click here to download the full size of the above Circuit.

the MP3302 are open load shut down, thermal shut down, under voltage lock out etc. Applications of Mp3302 are LED back lights, LED based lighting gadgets etc. Functional block diagram of the MP3302 is shown below (Fig1). The IC uses a constant current, peak current mode step up regulator scheme for regulating the current through the LEDs. At thebeginning of each oscillator cycle, the control circuitry switches the power MOSFET ON. For preventing sub harmonic oscillation, a stabilizing ramp signal is added to the current sense amplifiers output and the resultant signal is given to the non inverting input of the PWM comparator. When this resultant voltageis equal to the voltage at the PWM comparator`s inverting input (output voltage of the error amplifier), the power MOSFET is switched OFF. The error amplifier`s output is the difference between the feedback voltage and the reference voltage. When the output voltage drops, the feedback voltage also drops and this in increases the output of the error amplifier. This in turn increases duty cycle of the power MOSFET drive signal produced by the control circuitry which increase the duty cycle of the power MOSFET, it conducts more current and the output voltage is regulated. Circuit diagram of a 27 LED driver circuit using MP3302 is shown below (Fig 2). C1 is the input bypass capacitor and C2 is the output bypass capacitor. Resistor R1 is the feedback resistor and it controls the...

Leave Comment

characters left:

Related Circuits

  • New Circuits



    Popular Circuits

    VLF Radio Receiver circuit
    Noise limiter
    Universal Power Controller
    ICL7107 Digital LED Voltmeter
    LED (IR LED1) and the phototransistor (T1) and wireless light switch
    Heartbeat Sensor (Tranduscer)
    Frost Detector Temperature Sensor Circuit
    Amplifying DC Diode Detector Output
    simple 4 channel video amplifier
    Schematic Diagram 50W TK4036II baseed Stereo Power Amplifier Circuitand explanation
    PF Test Equipment
    Dolby IC CX1100 series and Application