L7987L

Voltage Regulators - DC DC Switching Regulators Overview

The L7987L is a monolithic asynchronous step-down switching regulator from STMicroelectronics, designed to deliver up to 2 A of DC output current. It operates with an input voltage range of 4.5 V to 61 V and provides an adjustable output voltage from 0.8 V to nearly the input voltage. The device features a typical RDS(ON) of 300 mΩ and supports an adjustable switching frequency between 250 kHz and 1.5 MHz. It includes low quiescent current modes, with typical values of 11 μA in shutdown and 1 mA during operation. The regulator incorporates pulse-by-pulse current sensing with digital frequency foldback for protection, an open-collector PGOOD output for sequencing, and a VBIAS pin switchover feature to maximize efficiency at light loads.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Asynchronous buck topology with integrated power MOSFET delivering 2 A continuous current
• Adjustable switching frequency from 250 kHz to 1.5 MHz for optimized component size
• VBIAS pin switchover mechanism to enhance light-load conversion efficiency
• Digital frequency foldback and peak current foldback for robust short-circuit protection

Voltage Regulators - DC DC Switching Regulators Applications

• Industrial automation systems requiring isolated or non-isolated DC-DC conversion
• Sensors with analog-to-digital conversion where synchronization prevents beating noise
• Programmable Logic Controller (PLC) solutions providing regulated voltages for MCUs and isolators
• General-purpose high-voltage step-down power supplies in compact form factors

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify the specific ordering suffix to confirm package type and reel configuration, as variations exist between tube and tape-and-reel packaging. Confirm RoHS compliance status through official datasheets or manufacturer declarations prior to integration. Ensure design compatibility with the HTSSOP-16 package thermal requirements, considering the exposed pad for heat dissipation. Cross-reference part numbers with authorized distributors to avoid counterfeit components and validate authenticity through STMicroelectronics verification channels.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select the L7987L when applications require a wide input voltage range up to 61 V with synchronous-like efficiency benefits via asynchronous operation. Choose this device if adjustable soft-start and current limit thresholds are needed to tailor startup behavior and protect downstream components. Consider the L7987L for designs requiring multiple units synchronized via the SYNCH pin to minimize electromagnetic interference in sensitive analog circuits. Evaluate the trade-off between external component count and efficiency gains provided by the VBIAS management feature.

Voltage Regulators - DC DC Switching Regulators Part Context

The L7987L belongs to the L7987 family of high-voltage step-down regulators manufactured by STMicroelectronics. It is categorized under Power Management ICs (PMIC) specifically within the Switching Voltage Regulators subcategory. The device is part of ST's portfolio aimed at industrial and automotive applications, offering robust protection features and high integration levels to simplify power supply design in space-constrained environments.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

Publicly confirmed substitute part numbers are not explicitly listed in the provided documentation. Designers should consult STMicroelectronics application notes or distributor cross-reference tools for compatible alternatives based on specific electrical and thermal requirements.