KA34063A

KA34063A is a monolithic integrated circuit in the PMIC - Voltage Regulators - DC DC Switching Regulators category. It is a PWM control DC/DC converter that has a wide range of application fields such as power supplies, as well as battery-powered equipment. The device is also capable of providing excellent low noise performance, making it a very attractive solution for many power-supply designs. This article will cover the application fields and working principle of KA34063A.

Application Fields

The KA34063A offers an integrated PWM flyback DC/DC converter, making it a great solution for applications where increased power efficiency, reduced component count and space saving are required. It is well suited for switching regulated power supplies, low power chargers, power management systems, as well as battery-powered equipment.

Its wide input range (3.3 to 40V) and high frequency operation (up to 500kHz) make the device very attractive in portable applications, such as mobile phones, notebook PCs and PDAs. The KA34063A is also capable of providing good efficiency up to 96% and excellent low noise performance.

Moreover, the KA34063A\'s adjustable current limit and overvoltage protection features ensure any external component connected to the device remains protected against surges and other unwanted events. Its reverse current blocking feature makes the device well suited for battery-powered applications, where a low dropout current is desired.

Working Principle

The KA34063A is a buck-boost converter, i.e., it can step down or up the voltage coming from the input sources depending on the need. The device is provided with two main parts; the top-half, which is the power stage comprising of power MOSFET, an error amplifier and an oscillator, and the bottom-half which is the controller, containing the compensator, current limit, WDT and PFD for the PWM.

The voltage across the input is compared to a predetermined level (set by the internal compensator) and once the difference reaches a certain threshold, a pulse-width modulated signal is delivered to the power MOSFET which, in turn, switch the powerMOSFET off, thereby disconnecting the output from the input. After the power MOSFET turn off, the power is transferred from the output to the input making the output voltage lower than the input. This action of PWM control is what makes the KA34063A a very efficient solution for many power supply designs.

The device also offers an adjustable current limit feature which can be used to limit the amount of current that is transferred to the output. In addition, the device can be programmed in either a discontinuous current mode (DCM) or a continuous current mode. The discontinuous current mode limits the effect of the inductor current on the supply voltage, while the continuous current mode helps to reduce the input ripple current.

In addition, the KA34063A adds a number of features such as overvoltage protection, reverse-current blocking, soft-start and a WDT timer, providing protection against under-voltage, over-voltage, over-temperature and over-current conditions.

Conclusion

The KA34063A is a monolithic integrated PWM control DC/DC converter with a wide range of application fields, including power supplies, battery-powered equipment and power management systems. The device is capable of providing good efficiency and excellent low noise performance, making it an attractive solution for many power-supply designs. It can be programmed in either a discontinuous current mode (DCM) or a continuous current mode and has a wide range of features such as adjustable current limit and overvoltage protection, providing protection against under-voltage, over-voltage, over-temperature and over-current conditions.