MAX8784ETL+T

MAX8784ETL+T application field and working principle

The MAX8784ETL+T is an advanced power management integrated circuit (PMIC). It belongs to the category of specialized PMICs, which are designed for more specific requirements.The MAX8784ETL+T is an adjustable, single-slot, low-noise, low-voltage, three-phase non-isolated synchronous buck converter. It is designed to provide higher efficiencies on modern servers, network switches and other critical applications.

The MAX8784ETL+T is deployed in server power supply applications which don\'t require isolation. This IC uses a low-noise, voltage-mode controller architecture and delivers up to 90% efficiency, reducing power consumption and offering significant cost and space savings. This IC is also optimized for high frequency, wide range applications and provides synchronous rectification capability.

Main Features

• Input voltage range: 4.5V to 16V
• Output voltage range: 0.5V to 5V
• Output current: 10A
• Output power: 55W
• Adjustable frequency range: 200kHz to 1.6MHz
• Switching frequency spread spectrum: 50kHz
• Peak efficiency up to 90%

Working Principle

The MAX8784ETL+T is a voltage-mode controller with an internal PMOS FET, which is connected to the output directly. In this non-isolated synchronous configuration, the voltage regulation is achieved through Pulse Width Modulation (PWM) and synchronous rectification. The internal PWM block is used to generate the switching signals and control the powertrain current/voltage loop. It contains an adjustable current limit, a voltage-loop comparator, and driver circuitry.

The PWM signal is modulated by the reference voltage, current limit, and feedback signal generated from the output. The rectifier synchronizes the input signal with the output signal using two MOSFETs in parallel, switching them at the same time. This synchronous configuration reduces switching losses, improves efficiency, and reduces EMI. The IC includes other features such as soft-start, under-voltage lock-out, over-temperature protection, and overcurrent protection.

Conclusion

The MAX8784ETL+T is a specialized power management integrated circuit (PMIC) designed for high-performance server power supply designs. It is an adjustable, single-slot, low-noise, low-voltage 3-phase non-isolated synchronous buck converter with an adjustable frequency range of 200kHz to 1.6MHz, switch frequency spread spectrum of 50kHz, and up to 90% peak efficiency. It is optimized for high-frequency and wide-range applications and provides synchronous rectification capability. The operating principles of this circuit are based on the voltage-mode control architecture, which enables the low-noise operation and achieves high efficiency.