ACT4070BYH-T

Application Field and Working Principle of ACT4070BYH-T

PMIC (Power Management IC) lie at the heart of complex systems, controlling power use and optimising performance. Voltage Regulatory ICs (also known as Voltage Regulators) are the most widely used PMICs. DC-DC Regulators (also known as DC-DC Switching Regulators) are a common type of voltage regulating IC used for transforming a voltage from one specific level to another. ACT4070BYH-T is one of such DC-DC Regulator.

Application Field

The ACT4070BYH-T is a step-down regulator, providing a regulated output of 5 V from input voltages between 6.5 V and 40 V, making it ideal for automotive and non-automotive applications including industrial 48 V systems. The regulator incorporates several features facilitating its use in auto boost topology, providing a solution that allows the required power output once the gate activity time is predetermined.

Its ultra-low quiescent current makes it a great choice for current-sensitive systems and no-load shutdown enables automatically saving power in such systems. Other features such as frequency spread spectrum and over-temperature protection make it suitable for automotive applications with stringent safety requirements as well.

Working Principle

The ACT4070BYH-T is a continuous conduction mode Buck switching regulator, and it works through the principle of Pulse Width Modulation (PWM). Its operating frequency is typically 300 kHz, with a switching frequency spread spectrum from 250 kHz to 350 kHz. By using PWM to modulate the conduction width of power MOSFETs, the input voltage is transformed into the required output voltage.

At the start of the cycle, a MOSFET carried by PWM signal turns on, and current begins to flow through the inductor while another MOSFET with the complimentary signal remains off. As the inductor current increases, a shunt regulator within the IC senses the current and ramps the drive signal until reaching a pre-defined peak current, when the drive signal turns off and the current is disabled, then the voltage output is established.

Conclusion

ACT4070BYH-T is a DC-DC switching regulator, which operates by Pulse Width Modulation (PWM) with a frequency spread spectrum from 250 kHz to 350 kHz. It provides a regulated output voltage of 5 V from the input voltages varying from 6.5 V to 40 V, being an ideal solution for industrial and automotive application where power saving is crucial. Its quiescent current and frequency spread noise spectrum features provide superior efficiency and make it ideal for use in highly sensitive systems.