LP38690SD-5.0: High-Performance 5V Linear Voltage Regulator by Texas Instruments

The LP38690SD-5.0 from Texas Instruments (TI) is a high-efficiency linear voltage regulator designed to deliver stable 5V power for demanding applications. Despite being marked as obsolete, it remains a preferred choice for engineers due to its reliability, compact design, and advanced features. This detailed guide covers its specifications, benefits, and applications to help you integrate it into your projects.

LP38690SD-5.0 Overview

The LP38690SD-5.0 is part of TI s renowned power management IC (PMIC) lineup. It provides a fixed 5V output with a 1A current capacity, making it ideal for microcontrollers, sensors, and communication modules. Its 6-WSON exposed pad package ensures superior thermal performance, while its low dropout voltage maximizes efficiency.

Key Features

• Input Voltage Range: Up to 10V
• Output Voltage: Fixed 5V ( 2% accuracy)
• High Current Output: 1A continuous
• Low Dropout Voltage: 0.8V at full load
• Ultra-Low Quiescent Current: 55 A (improves battery life)
• Excellent PSRR: 55dB at 120Hz (rejects input noise)
• Over-Temperature Protection: Prevents thermal damage
• Wide Operating Range: -40 C to +125 C

Applications

The LP38690SD-5.0 is widely used in:

• Industrial Automation: PLCs, motor controllers
• Consumer Electronics: Portable devices, IoT modules
• Embedded Systems: Raspberry Pi, Arduino peripherals
• Telecom Equipment: Routers, base stations

Why Choose the LP38690SD-5.0?

1. Reliability: TI s quality assurance ensures long-term stability.
2. Space-Saving: 6-WSON (3x3mm) package fits compact designs.
3. Energy-Efficient: Low quiescent current extends battery life.
4. Thermal Resilience: Exposed pad dissipates heat effectively.

Technical Deep Dive

1. Electrical Performance

With a dropout voltage of just 0.8V at 1A, the LP38690SD-5.0 outperforms competitors in efficiency. Its 55dB PSRR ensures clean power delivery even in noisy environments.

2. Thermal Management

The exposed-pad WSON package reduces thermal resistance ( _JA = 42 C/W), allowing operation at high ambient temperatures without derating.

3. Protection Mechanisms

Built-in over-temperature shutdown safeguards against overheating, while reverse-polarity protection enhances durability.

Design Considerations

• Input Capacitor: Use a 1 F ceramic capacitor (X7R) near the input pin.
• Output Capacitor: A 10 F ceramic capacitor ensures stability.
• PCB Layout: Maximize copper area under the exposed pad for heat dissipation.

Alternatives and Cross-References

For newer designs, consider TI s TPS7A05 (500mA) or LP5907 (250mA) for ultra-low-noise applications. Cross-reference with ON Semiconductor s NCP1117 for pin-compatible options.

Where to Buy

Despite its obsolete status, we stock genuine LP38690SD-5.0 units with traceable TI certifications. Contact us for bulk pricing or samples.

Conclusion

The LP38690SD-5.0 remains a robust solution for 5V regulation, combining TI s engineering excellence with practical performance. Its balance of efficiency, thermal management, and protection makes it a timeless choice for legacy and new designs alike.

Need this IC for your project? Order now or explore our similar products for upgraded alternatives.