LM140K-12

Overview

The LM140K-12/NOPB is a fixed-output linear voltage regulator from Texas Instruments, providing a stable 12 V output with a maximum load current of 1 A. It operates within an extended temperature range of -55 °C to +125 °C and features a typical power supply rejection ratio (PSRR) of 72 dB. The device exhibits a line regulation of 18 mV and a load regulation of 32 mV, with a quiescent current of 6 mA. Packaged in a TO-3-2 through-hole case, it serves as a robust three-terminal positive regulator for industrial applications requiring reliable DC power conversion.

Feature Summary

• Provides a fixed 12 V regulated output suitable for standard logic and analog circuits
• Supports up to 1 A continuous load current for moderate power applications
• Operates reliably across an extended industrial temperature range from -55 °C to +125 °C
• Features high power supply rejection ratio to minimize noise on the output

Applications

• Industrial control systems requiring stable voltage rails
• Test and measurement equipment power supplies
• Automotive electronics operating in harsh thermal environments
• General-purpose linear regulation in embedded systems

Procurement Notes

Verify the specific suffix (e.g., NOPB) against the datasheet to confirm lead-free compliance and package variant. Ensure the TO-3-2 through-hole mounting style matches the target PCB design. Confirm that the 1 A current rating and 12 V fixed output align with the system's power budget and thermal dissipation capabilities before finalizing procurement.

Selection Notes

Select this component when a fixed 12 V output is required with high current capability and wide temperature tolerance. The TO-3-2 package offers superior thermal performance compared to smaller surface-mount alternatives, making it suitable for applications where heat dissipation is critical. Verify input voltage headroom to ensure proper dropout operation under all load conditions.

Part Context

This part belongs to the LM140 series of three-terminal positive regulators manufactured by Texas Instruments. The 'K' designation indicates military-grade reliability and extended temperature range, while '12' specifies the fixed 12 V output voltage. The NOPB suffix denotes a non-pb (lead-free) product compliant with RoHS standards, ensuring environmental safety without compromising electrical performance.

Replacement Considerations

Public confirmed substitute part numbers are not available in the provided documentation.