LH163T07

The LH163T07 devices are high voltage, high performance, 400V, 6A, 75mΩ, current-mode PWM controllers in flyback topology, suitable for various AC/DC adapter applications.

Power topology is a kind of switching power supply circuit, it efficiently converts one kind of electric energy into another kind, in order to meet the needs of the load. The switching power supply’s main components are the transformer, resonant inductor, rectifier and filter, and the switch unit. According to the input and output properties of the switching power supply, it can be divided into several categories, including full-bridge, half-bridge, push-pull, flyback, etc. The flyback switch power supply is the most important and widely used.

The flyback switch power supply is to use the instantaneous flyback effect of the inductor to boost the output voltage of the power supply. The LH163T07 is a current mode device with over-current detection and active power limitation function. The working principle of the LH163T07 mainly consists of current control, power limitation control, frequency control, etc.

The basic operation of LH163T07 is to connect the ceramic capacitor connected between the COMP pin and the FB pin to form a voltage divider network so that to determine the input duty cycle. When the voltage on the FB pin is lower than the input voltage on the COMP pin, the output voltage of the lower power transistor of the MOSFET pair is zero, and the upper MOSFET switch starts to conduct, which charges the inductor with current. When the inductor current reaches the predetermined OCP level, the LH163T07 will shut down the upper MOSFET, and then the secondary diode of the flyback switch output rectifies the voltage on the inductor, and then the filter capacitance is used to form the final output voltage.

The LH163T07 devices are used in many kinds of application fields, such as the AC-DC adapters that convert AC line input to DC output, LCD TV and the monitor power adapter application. It is able to regulate the output power of the supply with accurate output voltage and current levels. In addition, LH163T07 integrated over current protection, short circuit protection, over temperature protection and OVP protection functions, providing full protection and high reliability.

In conclusion, LH163T07 is a PWM controller with high voltage and high performance, and it is suitable for various AC / DC adapter applications. Its working principle is based on over-current protection, power limitation control, frequency control, etc. Its application fields cover a wide range, such as AC-DC adapters, LCD TV, monitor power adapters, etc.