MAX5067ETH-T

Application Field and Working Principle of MAX5067ETH-T

The MAX5067ETH-T is an advanced, integrated, adaptive-pulse-width modulation (APDT) DC-DC switching controller designed to control step-up/step-down converters used in industrial, automotive, computing and telecom applications. It is designed to provide low-cost and reliable power conversion in a small, thermally enhanced TQFN package. The MAX5067ETH-T is capable of delivering up to 6A on the output stage with a peak efficiency of 98%. The controller is well suited for applications such as ultra-low power, high bandwidth, low noise, non-isolated point-of-load converters.

Features

• Current-mode APDT control with output soft-start
• Single-stage regulator with continuous or discontinuous operation
• 2.8 V to 5.5 V supply voltage
• Programmable operating frequency (100 kHz to 300 kHz)
• Power good indicator (PGOOD)
• Compact, thermally enhanced TQFN package

Applications

• High performance DC-DC buck and boost converters
• Ultra low noise point-of-load (POL) converters
• On-board DC-DC converter designs
• Industrial, automotive, computing and telecom applications

Working Principle

The MAX5067ETH-T integrates an increase/decrease type step-up/step-down regulator in a single IC. This kind of integrated regulator saves component count, component cost, and board space. It also allows users to take advantage of the improved performance offered by the integrated regulator.

The internal circuit starts with a current mode control system, which utilizes an internal PLL to control the frequency and duty cycle under the given feedback input. This PLL allows the internal loop to be sensed very quickly, which translates into faster response times with no lag or transient overshoot. This controller is also equipped with a variable frequency that can be set manually via external resistor dividers, allowing for ultra-low noise operation. The duty cycle of the internal loop is then adjusted based on the feedback, which is used to generate a variable rate for the output stage.

The output stage combines a power MOSFET, control circuitry, and an associated protection device. The power MOSFET is a low RDS(ON) device which delivers high current output, while the protection device keeps the output stage safe from over-current conditions. The control circuitry adjusts the pulse width of the output stage based on the feedback, keeping the output at the desired voltage.

The MAX5067ETH-T is also capable of providing soft-start functionality by increasing the frequency and/or duty cycle at the turn-on. This feature allows the DC-DC converter to start smoothly and minimize any inrush current at startup. It is also capable of providing power good indication based on the output voltage. This feedback allows the user to know the status of the power output.

Conclusion

The MAX5067ETH-T offers a cost-effective solution for power conversion applications, with its integrated regulator, variable frequency, and soft-start features. Its high current output, compact form factor, and robust protection make it well suited for industrial, automotive, computing, and telecom applications. Its APDT control system and variable frequency capabilities also make it an ideal solution for ultra-low noise, high-bandwidth point-of-load converter designs.