LTC7860HMSE#PBF

Overview

The LTC7860HMSE#PBF is a high-efficiency synchronous buck controller designed for board-mount surge protection applications. It operates with an input voltage range of 4V to 140V and features a switching frequency adjustable from 250kHz to 1MHz. The device integrates a 3A peak current sink/source driver, enabling the use of low RDS(on) external N-channel MOSFETs. Key electrical parameters include a quiescent current of 1.2mA during operation and a shutdown current of less than 1µA. It supports output voltages down to 0.9V and includes programmable soft-start, cycle-by-cycle current limit, and overvoltage protection. The component is housed in a thermally enhanced 16-MSOP package.

Feature Summary

• Integrated high-side and low-side gate drivers capable of sourcing and sinking significant peak currents to minimize conduction losses.
• Built-in transient suppression circuitry that actively clamps input voltage spikes during load dump or cold crank events.
• Programmable switching frequency allows optimization for efficiency versus component size requirements.
• Comprehensive protection features including thermal shutdown, undervoltage lockout, and short-circuit protection.

Applications

• Automotive power distribution systems requiring robust surge immunity
• Industrial control modules exposed to harsh electrical environments
• Avionics power supplies needing compliance with strict transient standards

Procurement Notes

Verify the specific suffix and tape/reel or tube packaging configuration against the official Analog Devices datasheet before ordering. Confirm that the MSOP-16 package variant matches the thermal pad requirements of the target PCB layout. Ensure that the operating temperature range aligns with the intended application environment, as automotive-grade variants may have different qualification standards. Cross-reference the latest PCN documents for any material or assembly changes.

Selection Notes

Select this controller when designing systems that must withstand high-voltage transients up to 140V while maintaining efficient DC-DC conversion. Consider the external MOSFET selection carefully, as the driver's current capability dictates the optimal RDS(on) for minimizing heat dissipation. Evaluate the required switching frequency based on the available inductor and capacitor sizes. Ensure that the input source can handle the initial inrush current during soft-start without causing system-wide voltage droop.

Part Context

The LTC7860 belongs to Analog Devices' family of high-voltage synchronous buck controllers specifically engineered for surge stopper applications. It differs from standard buck controllers by integrating specialized circuitry to handle extreme input voltage spikes common in automotive and industrial settings. This integration reduces the need for external bulky protection components, allowing for more compact and reliable power supply designs compared to traditional discrete solutions.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation. Users should consult the official Analog Devices website for the most current replacement recommendations or pin-compatible alternatives within the same product family.