PM6686TR

Overview

The PM6686TR is a dual step-down controller designed for notebook PC power systems, featuring lossless current sensing and constant on-time architecture. It operates within an input voltage range of 5.5 V to 28 V and provides two adjustable output channels (OUT1: 0.7 V to 5.5 V; OUT2: 0.7 V to 2.5 V) with ±1.5% accuracy. The device includes an embedded linear regulator delivering up to 200 mA during switchover, selectable pulse skipping for light-load efficiency, and a minimum switching frequency of 33 kHz to prevent audio noise.

Feature Summary

• Dual step-down control with lossless current sensing and constant on-time architecture for fast transient response
• Embedded linear regulator with switchover capability providing up to 200 mA output current
• Selectable pulse skipping mode to enhance efficiency at very light loads
• Configurable minimum switching frequency of 33 kHz to eliminate audible noise

Applications

• Notebook PC chipset power supply design
• Multi-rail DC-DC conversion systems
• Battery-powered portable electronics requiring high efficiency

Procurement Notes

Verify the specific suffix 'TR' indicates tape-and-reel packaging when ordering. Confirm that the application circuit supports the required input voltage range of 5.5 V to 28 V. Ensure thermal management aligns with the 32-VFQFN package specifications. Check for RoHS3 compliance requirements if applicable to your manufacturing process. Validate that the selected switching frequencies meet electromagnetic interference constraints.

Selection Notes

Select this component when designing dual-output buck converters for portable computing devices. It is suitable for applications requiring independent power good signals and latched over-voltage/under-voltage protection. Consider the integrated LDO for auxiliary rails if bypassing is not preferred. Verify that the external MOSFET R DS(on) values are compatible with the lossless sensing technique for accurate current limiting.

Part Context

This part belongs to the PM6686 family of power management ICs from STMicroelectronics. It is specifically engineered for notebook computer architectures, offering a compact solution for generating multiple core and I/O voltages. The device integrates advanced control features to optimize power consumption across various load conditions while maintaining system stability.

Replacement Considerations

The PM6680TR is a related dual step-down controller in the same product family. Verify compatibility regarding input voltage ranges, output configurations, and pin assignments before substitution. Review datasheet differences for variations in quiescent power and reference voltage accuracy.