RT9618GS

RT9618GS is a DC-DC Buck (step-down) Controller IC with integrated high-side MOSFET and PGOOD Verification Monitor, designed to operate in the synchronous rectification mode to deliver high efficiency conversion. It supports output voltage range from 0.6V to 5.0V with very few Negative Temperature Coefficient (NTC) parts. The RT9618GS also includes many advanced functions such as programmable output voltage and over-current protection, automatic duty cycle control, internal soft start and a multiple system power on reset for power supply sequencing.

Application Field

The RT9618GS is the best choice for many switching power supplies in consumer, home appliance, office automation and industrial applications. It is intended to deliver high efficiency, low power consumption, and high performance in the most demanding portable equipment, such as mobile phones, PDAs, digital cameras, camcorders, DVD players, automotive applications and LCD TV.

Working Principle

The DC-DC switching can be implemented with RT9618GS IC. It is designed to switch the Input DC power source to the output load. It contains a voltage regulator and logic circuits that control the switching of an external power MOSFET to efficiently regulate the output voltage. The RT9618 operates in a continuous-conduction or synchronous mode. it works by switching the power transistor between a charging and an output phase. The power is transferred from the input to the output by switching off the switching transistor and allowing the inductance of the power transformer to store the energy and drive the output.

The RT9618GS uses a PWM (pulse width modulation) regulator modulator to drive the power transistorswitching. It controls the duty cycle of the PWM signal to adjust the voltage applied to the output.The RT9618GS has additional features such as a programmable over-current protection circuit and an over current protection circuit. The overcurrent protection circuit can be programmed to reduce the overcurrent rating of the MOSFET to the rated transistor level.