PM6680ATR

Overview

The PM6680ATR is a dual synchronous step-down controller designed for embedded computer systems, manufactured by STMicroelectronics. It features an input voltage range of 6V to 36V and provides two adjustable output channels with voltage ranges of 0.9V to 5V and 0.9V to 3.3V respectively. The device operates within a temperature range of -40°C to 125°C and utilizes a 32-VFQFPN (5x5) surface-mount package. Key electrical parameters include a selectable minimum switching frequency of 33kHz in pulse skip mode, a maximum quiescent power of 5mW, and an internally fixed soft-start time of 2ms. The controller incorporates lossless current sensing using low-side MOSFETs RDS(on) and includes an embedded LDO delivering up to 100mA peak current at 5V.

Feature Summary

• Dual synchronous buck architecture with constant on-time control for fast load transient response
• Lossless current sensing technique utilizing low-side MOSFETs RDS(on)
• Selectable pulse skipping operation to enhance efficiency at light loads and avoid audio noise
• Integrated thermal shutdown protection and independent power good signals

Applications

• Embedded computer system power management
• Multi-output DC-DC conversion for chipset power supplies
• Point-of-load converters requiring high efficiency at light loads

Procurement Notes

Verify the specific suffix 'A' indicates the automotive-grade or extended temperature variant (-40°C to 125°C) compared to the standard PM6680TR. Confirm the 32-VFQFPN package dimensions match the design footprint. Ensure input voltage requirements do not exceed the 36V maximum limit specified for this variant. Check moisture sensitivity level (MSL 3) handling requirements during assembly.

Selection Notes

Select the PM6680ATR when operating environments require extended temperature coverage up to 125°C. Choose this model over the PM6680TR if the application demands an input voltage range extending to 36V. Consider this controller for designs prioritizing light-load efficiency through selectable pulse skipping modes. Verify that the required output voltage ranges align with the 0.9V-5V and 0.9V-3.3V specifications.

Part Context

The PM6680ATR belongs to the PM6680 family of dual step-down controllers from STMicroelectronics. It shares the core constant-on-time architecture and lossless sensing technology with other variants but differs in operational temperature range and input voltage limits. This component serves as a central power management unit for complex embedded systems requiring multiple regulated rails from a single battery source.

Replacement Considerations

PM6680TR: Standard industrial grade version with lower max input voltage (28V) and narrower temperature range (0°C to 85°C). PM6680A: Non-trimmed variant available in different packaging options.