AM6685HLB

Overview

The AM6685HLB is a dual step-down controller designed for high-efficiency power conversion. It features an embedded integrator control loop to compensate DC voltage error from output ripple and utilizes pulse skipping techniques to enhance efficiency at very light loads. The device supports selectable switching frequencies of 200 kHz/300 kHz, 300 kHz/400 kHz, or 400 kHz/500 kHz for its 5 V and 3.3 V sections. It operates within a 6 V to 28 V input voltage range and provides fixed 5 V and 3.3 V outputs capable of delivering 100 mA peak current. A 1.230 V ±1% reference voltage is available, alongside lossless current sensing using low-side MOSFETs' R DS(on).

Feature Summary

• Constant on-time architecture ensures fast load transient response.
• Embedded voltage feed-forward provides nearly constant switching frequency operation.
• Negative current limit and soft-start internally fixed at 2 ms.
• Latched overvoltage protection (OVP) and undervoltage protection (UVP).

Applications

• High efficiency DC-DC conversion systems
• Power supplies requiring low quiescent power
• Applications needing audio noise avoidance via selectable minimum frequency

Procurement Notes

Verify the exact manufacturer designation for the part number AM6685HLB, as primary documentation references the PM6685 series. Confirm package type and temperature grade specifications against official datasheets before integration. Ensure compatibility with external components such as inductors and capacitors based on the selected switching frequency configuration.

Selection Notes

Select this component when designing dual-output power stages requiring independent power good signals and output voltage ripple compensation. Consider the selectable pulse skipping mode for applications prioritizing efficiency at light loads. Evaluate the need for specific switching frequency options to balance EMI performance and component size requirements.

Part Context

This device belongs to a family of dual step-down controllers focused on providing extremely high efficiency conversion through loss-less current sensing techniques. The design emphasizes robust protection features and flexible operating modes to suit various industrial and consumer electronics power management needs.

Replacement Considerations

Consult official manufacturer documentation for confirmed substitute part numbers. Verify pinout compatibility and electrical parameter equivalence before considering any alternative components.