MC34063ACN

MC34063ACN is a DC/DC switching regulator which belongs to the Power Management IC (PMIC) voltage regulator family, more specifically to the DC DC switching regulator category. The main purpose of this device is to generate accurate output voltage from low voltage input source such as battery and an unregulated voltage source. It is widely used in various applications such as automotive, management, industrial and telecommunications, as well as other high-performance applications.

Applications

MC34063ACN is specifically designed for solar panels, LED and LCD backlight drives and other high-performance applications. It is a popular response to traditional and costly linear regulators, as it can provide higher efficiency, resulting in lower power consumption, cooler operation and longer battery life.

In LCD displays, the MC34063ACN is a cost-effective device for controlling the LED backlight current, whether it is a single LED or an RGB LED array. By configuring the slew rate and current limit values, designers can control the LED current precisely, achieving an optimal backlight intensity, an important factor in ensuring high image quality.

In automotive environment, the MC34063ACN can also be used for fuel gauge, reversing camera, infotainment system and power management. In communications, the MC34063ACN can be used for modems and signal conditioners, and in industrial environment, it can be used in power supplies and high power amplifiers.

Working Principle

The MC34063ACN is a monolithic control circuit consisting of an improved version of pulse width modulator (PWM) with a comparator, an oscillator, a logic circuit and a transformer driver. By using only a few external components, such as an inductor and capacitors, designers can transform a raw DC voltage into a low-ripple DC voltage. The internal voltage reference circuit provides user the possibility to regulate the output voltage.

The operation of the MC34063ACN is activated by applying an external voltage source to the Vin pin. The switching frequency at which the device operates is determined by connecting a resistor between the RT pin and GND as well as a capacitor between Cpin and GND according to the following equation:

where RT is the resistor in kOhm, C is the capacitor in pF and τ is the constant 0.693.

When Vin voltage rises above the internal analog reference voltage (1.25V typ.), the error amplifier output is set to its upper limit, turning the N-MOSFET on and the P-MOSFET off. The inductor then stores the energy in its magnetic field. When the input voltage comes down, the error amplifier output is set to its lower limit turning the N-MOSFET off and the P-MOSFET on, causing the stored inductor energy to be released, transforming to Vo voltage.

Conclusion

The MC34063ACN is an excellent choice for designers who require higher efficiency and lower power consumption without sacrificing performance and reliability. It offers a cost-effective solution for solar panels, LED and LCD backlight drive and battery applications. Furthermore, the working principle of this device is also clearly defined, making it relatively easy to design with.