L4940V12

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Overview

The L4940V12 is a three-terminal positive linear regulator from the L4940 series, manufactured by STMicroelectronics. It provides a fixed 12 V output with a maximum load current of 1.5 A and features a typical dropout voltage of 450 mV at 1 A. The device incorporates internal current limiting, thermal shutdown, and reverse polarity protection. It operates within an input voltage range up to 17 V and supports junction temperatures from -40 °C to +150 °C. Available in TO-220, TO-220FP, and D2PAK packages.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Feature Summary

• Very low dropout voltage for efficient battery-powered applications
• Internal current limiting and anti-saturation circuitry
• Thermal shutdown and safe area protection
• Reverse polarity protection on the input

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Applications

• Industrial equipment power regulation
• Consumer electronics power supplies
• Battery-powered systems requiring extended life
• Distributed supply on-card regulation

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Procurement Notes

Verify component authenticity through authorized channels as the L4940 series may have limited availability or end-of-life status. Confirm package type (TO-220, TO-220FP, or D2PAK) matches design requirements. Ensure compliance with RoHS3 specifications if environmental standards are mandatory. Review datasheet revision history for any updates to electrical characteristics or mechanical dimensions before finalizing procurement.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Selection Notes

Select the L4940V12 when a stable 12 V rail is required with high current capability up to 1.5 A. Consider the TO-220 package for through-hole mounting or D2PAK for surface mount applications. Evaluate thermal resistance values to ensure adequate heat dissipation under maximum load conditions. Verify that the input voltage remains within the 17 V limit while maintaining sufficient headroom for the specified dropout voltage.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Part Context

The L4940V12 belongs to the L4940xx family of very low drop 1.5 A regulators. This series includes variants with fixed outputs of 5 V, 8.5 V, 10 V, and 12 V. All members share identical pin configurations and protection features, differing primarily in their regulated output voltage levels. The family is designed for industrial and consumer applications requiring reliable linear regulation.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators Replacement Considerations

Direct substitutes include other L4940xx variants such as L4940V10 or L4940V85 if different voltage rails are acceptable. Cross-referencing with similar 1.5 A LDOs from other manufacturers requires verification of pin compatibility and thermal performance. Ensure replacement parts meet the same safety certifications and operating temperature ranges.

Voltage Regulators - Linear, Low Drop Out (LDO) Regulators FAQ

What is the maximum input voltage for the L4940V12?

The maximum forward input voltage is 17 V.

Does the L4940V12 support reverse polarity connection?

Yes, the device includes internal reverse polarity protection diodes.

What packages are available for this part number?

The L4940V12 is available in TO-220, TO-220FP, and D2PAK packages.