L5989D

Voltage Regulators - DC DC Switching Regulators Overview

The L5989D is a monolithic step-down switching regulator from STMicroelectronics, designed to deliver a continuous output current of 4 A and pulsed currents exceeding 5 A. It operates with an input voltage range of 2.9 V to 18 V and provides an adjustable output voltage from 600 mV to 18 V. The device features an internal switching frequency adjustable between 100 kHz and 1 MHz via an external resistor. It utilizes a high-side PMOS switch for 100% duty cycle operation without requiring an external bootstrap capacitor. The component is housed in an HTSSOP-16 package and supports operating temperatures from -40°C to +150°C.

Voltage Regulators - DC DC Switching Regulators Feature Summary

• Integrates a high-side PMOS switch enabling 100% duty cycle operation without external bootstrap capacitors.
• Features a multifunction UOS pin for configurable UVLO thresholds, selectable OVP protection modes, and soft-start sink capability control.
• Includes comprehensive protection mechanisms such as constant current protection during soft-start, hiccup mode triggering, and adjustable current limit tracking.

Voltage Regulators - DC DC Switching Regulators Applications

• Automotive systems requiring robust power regulation within wide input voltage ranges
• Industrial applications demanding high reliability and thermal performance
• Systems needing flexible input bus compatibility (3.3 V, 5 V, or 12 V)

Voltage Regulators - DC DC Switching Regulators Procurement Notes

Verify the specific ordering suffix and package variant against the official datasheet to ensure compatibility with your design requirements. Confirm that the component status aligns with your production timeline, as availability may vary. Cross-reference the pinout and electrical specifications with your schematic to prevent integration errors. Ensure that thermal management solutions meet the device's dissipation needs under maximum load conditions.

Voltage Regulators - DC DC Switching Regulators Selection Notes

Select this regulator when a high continuous current of 4 A is required with an input voltage up to 18 V. It is suitable for designs needing adjustable switching frequencies up to 1 MHz to optimize filter size. Consider this part if the application benefits from integrated UVLO and OVP configurations via the UOS pin. Ensure the system can accommodate the HTSSOP-16 package and meets the thermal constraints for the specified current output.

Voltage Regulators - DC DC Switching Regulators Part Context

The L5989D belongs to the L5989D series of monolithic step-down power switching regulators manufactured by STMicroelectronics. It is categorized under Switching Voltage Regulators and falls within the broader PMIC - Power Management ICs subcategory. This component is part of ST's portfolio of buck converters designed for automotive and industrial applications, emphasizing high performance and flexibility.

Voltage Regulators - DC DC Switching Regulators Replacement Considerations

Check for direct substitutes within the L5989 family or other ST buck converters with similar 4 A output and 18 V input ratings. Verify pin-to-pin compatibility and electrical parameter alignment before substitution. Consult official replacement guides for discontinued or end-of-life components.

Voltage Regulators - DC DC Switching Regulators FAQ

How is the switching frequency adjusted on the L5989D?

The internal switching frequency is adjustable by an external resistor and can be set continuously from 100 kHz to 1 MHz.

What protection features are included in the L5989D?

The device includes overcurrent protection with hiccup mode, overvoltage protection (selectable latched or non-latched), undervoltage lockout, and thermal shutdown.

Can the L5989D operate at 100% duty cycle?

Yes, the device is capable of 100% duty cycle operation thanks to the embedded high-side PMOS switch which does not require an external bootstrap capacitor.