UC2855ADWTRG4

UC2855ADWTRG4 PMIC - PFC Application Field and Working Principle

Power factor correction (PFC), is a type of electrical technology that is used to improve the power factor (PF) of a power source, which is the ratio between the real power and the apparent power, supplied to the source. The UC2855ADWTRG4 is a high-efficiency, low-power, cost-effective PFC controller designed for AC-DC and DC-DC power applications.

Application Field

The UC2855ADWTRG4 allows for a wide range of applications due to its high-efficiency performance and low-power nature. It is suitable for switching power supplies and AC-DC or DC-DC converters. The controller can work over a wide input voltage range with a low voltage overhead (less than 0.8 V), which allows the device to be used in applications that require lower voltages such as LED lighting, portable electronics, and switch-mode power supplies.

Working Principle

A PFC controller, such as the UC2855ADWTRG4, operates by pulse width modulation control, which is when an analog control signal is used to modulate the width of a series of pulses that controls a power device. The control signal is generated from a phase-shifted zero-crossing method, where a signal is generated from the phase difference between the input voltage and the output current. The signal is then used to obtain a pulse width modulation control. The controller also provides overload protection by shutting off the output in cases of a single overload or short circuit.The UC2855ADWTRG4 uses an internal error amplifier to provide a high-precision line and load regulation, which helps maintain the power factor and stability of the system. The UC2855ADWTRG4 also provides a low-noise surge rejection to reduce surges from the line voltage, thus reducing the number of disturbances and improving the stability of the system.

Conclusion

In conclusion, the UC2855ADWTRG4 is a high-efficiency, low-power PFC controller that is suitable for a wide range of applications including LED lighting, portable electronics, and switch-mode power supplies. The controller operates by pulse width modulation control and provides overload protection, a high-precision line and load regulation, and low-noise surge rejection which helps maintain the power factor and stability of the system.