Texas Instruments LM3485 PFET Buck Controller IC, 4.5V to 35V, VSSOP-8

The Texas Instruments LM3485MM/NOPB is a high-performance hysteretic non-synchronous PFET buck controller, engineered to simplify the design of compact and efficient step-down switching regulators. Its innovative architecture is ideal for a diverse array of applications, providing a robust and straightforward solution for power management challenges. The hysteretic control method eliminates the need for complex control loop compensation, allowing for stable operation with a wide selection of external components, which significantly accelerates development time.

A key advantage of this PFET-based controller is its ability to deliver ultra-low dropout and support 100% duty cycle operation, enabling the regulator to maintain regulation even when the input voltage approaches the output voltage very closely. This feature is particularly valuable in battery-powered systems, extending usable battery life. Furthermore, the design maintains high efficiency at light loads without the typical trade-off of increased output ripple, contributing to superior overall system performance and lower power dissipation.

Built-in cycle-by-cycle current limit protection enhances system reliability. This protection is implemented by measuring the voltage across the PFET's own RDS(ON), cleverly removing the requirement for an external current-sense resistor. The current limit threshold is easily adjustable with a single external resistor, allowing designers to tailor protection for safe operation across different output current requirements. The device is also designated as a green product, manufactured with no antimony or bromine (no Sb/Br).

Key Features & Specifications:

• Control Methodology: Easy-to-use hysteretic control.
• Efficiency: Delivers up to 93% high efficiency.
• Duty Cycle: Supports 100% duty cycle for ultra-low dropout operation.
• Protection: Integrated current limit.<