STMicroelectronics L6981N50DR 线性稳压器，SOIC8 封装，适用于工业和物联网

STMicroelectronics L6981N50DR Fixed 5V Linear Regulator Overview

The STMicroelectronics L6981N50DR is a high-reliability fixed 5V linear voltage regulator engineered for low-noise, stable power management in B2B industrial automation, Internet of Things (IoT), and home appliance applications. Designed to convert 7V?C25V input voltages to a precise 5V output-critical for powering noise-sensitive components like industrial sensors, IoT data loggers, and home appliance display modules-it integrates a low-dropout (LDO) control circuit, overcurrent protection, and thermal shutdown into a compact SOIC8 surface-mount package. With an operating temperature range of -40??C to +125??C and support for 1A continuous output current, it maintains consistent performance in harsh, space-constrained environments-making it a top choice for engineers prioritizing simplicity, low noise, and 24/7 reliability in low-to-mid power systems.

As a trusted product from STMicroelectronics-a global leader in semiconductor innovation with decades of expertise in industrial-grade power solutions-the L6981N50DR meets strict quality standards (including RoHS 2 certification and ISO 9001 compliance) and undergoes rigorous testing for long-term durability. Senior engineers at a leading industrial sensor firm endorse it, noting: ??The L6981N50DR??s fixed 5V output and low noise let us power our precision pressure sensors without extra filtering, while the SOIC8 package cuts our PCB space by 30% vs. older DIP regulators.?? For more reliable industrial and IoT ICs, visit 集成电路制造商.

Technical Parameters of L6981N50DR

Key Technical Features of L6981N50DR

• 固定 5V 输出，精度为 2%, eliminating the need for external voltage adjustment components and ensuring consistent power for 5V-specific devices. An industrial sensor engineer reported this feature ??cut our component count by 20%, as we no longer need trimmers to calibrate voltage-saving 10% PCB space and 15% assembly time.??
• 7V?C25V wide input range, accommodating diverse power sources (12V factory supplies, 24V industrial batteries) without external voltage clamping. A home appliance designer noted ??this range lets us use the same regulator across 3 product lines, standardizing our inventory and cutting logistics costs by 25%.??
• SOIC8 package with exposed thermal pad, balancing space efficiency (30% smaller than DIP8 packages) and heat dissipation (25% better than standard SOIC8 packages without pads). IoT data logger teams confirm ??this package fits in 4.9mm x 3.9mm PCB slots while keeping the regulator 15??C cooler at 1A output-critical for compact battery-powered devices.??
• Low output noise (??30??V_rms), preventing signal interference for noise-sensitive components like industrial ADCs and IoT transceivers. A sensor manufacturer noted ??this noise level reduced measurement errors in our temperature sensors by 96%, meeting our clients?? ISO 9001 quality requirements without extra filtering chips.??
• 0.5V low dropout voltage, maintaining stable 5V output even when input voltage drops to 7.5V (e.g., during battery discharge). An IoT firm shared ??this dropout lets our data loggers operate until batteries reach 7.5V (vs. 9V with older regulators), extending battery life by 25%-critical for remote deployments.??

Advantages of L6981N50DR Over Alternative Solutions

Compared to adjustable linear regulators, larger-package alternatives (e.g., DIP8), and high-noise switching regulators, the L6981N50DR delivers three critical benefits for B2B low-noise, stable power designs-backed by real customer feedback:

First, its fixed 5V output simplifies design vs. adjustable regulators. Adjustable regulators require external resistors to set voltage, adding components, PCB space, and calibration time. The L6981N50DR??s pre-set 5V output eliminates this work. An industrial automation designer explained: ??Our old adjustable regulator needed 2 extra resistors and 1 trimmer; switching to this model cut component count by 20%, saving 10% PCB space and 15% assembly time. We also reduced voltage calibration errors by 95%.??

Second, its SOIC8 package solves space challenges vs. DIP8 alternatives. DIP8 through-hole packages (19.05mm x 6.35mm) take 4x more PCB space than the 4.9mm x 3.9mm SOIC8, making them unsuitable for compact designs. The SOIC8??s surface-mount format also enables denser PCB layouts. A home appliance firm confirmed ??our old DIP8 regulator needed a 20mm x 10mm PCB slot; this SOIC8 fits in 5mm x 5mm-critical for our slim washing machine control board. This also reduced appliance weight by 30%, improving shipping efficiency.??

Third, its low output noise outperforms switching regulators. Switching regulators typically have 100?C500??V output noise, which interferes with sensor signals and data transmission. The L6981N50DR??s ??30??V noise eliminates this issue. An industrial sensor designer shared ??our old switching regulator??s 200??V noise caused 25% of sensor data to be unusable; this model cuts noise by 85%, meeting client accuracy requirements. We also removed 2 external filters, saving 15% PCB space and 10% component cost.??

Typical Applications of L6981N50DR

The L6981N50DR is engineered to solve low-noise, stable power regulation challenges-with proven success in these key B2B use cases:

• Industrial Automation (Precision Sensors): Converting 12V factory power to 5V for pressure and temperature sensors. A factory operator confirmed ??low noise reduces measurement errors by 96%, and 1A output powers 3 sensors-sensor node uptime improved to 99.99% vs. 99.8% with old regulators.??
• Internet of Things (IoT) Data Loggers: Regulating 12V battery power to 5V for microcontrollers and memory modules. An IoT provider noted ??wide input range lets loggers use 24V industrial batteries, and low dropout extends battery life by 25%-remote deployment costs dropped by 30%.??
• Home Appliances (Smart Refrigerators): Step-down 12V AC DC adapter power to 5V for display panels and door sensors. A home tech brand reported ??SOIC8 package fits in slim control boards, and fixed 5V output cuts component count by 20%-appliance cost reduced by 12%.??
• 安全与监控（无线运动传感器）: Converting 12V POE power to 5V for detection modules. A security firm confirmed ??low noise ensures reliable motion detection, and 1A output powers sensors 24/7-false alarms dropped by 80% vs. high-noise regulators.??
• 测试与测量（便携式信号发生器）: Regulating 9V battery power to 5V for signal circuits. A test equipment maker shared ????2% voltage accuracy ensures signal precision, and small SOIC8 package reduces tool weight by 20%-improving field usability for technicians.??

常见问题（FAQ）

Why is fixed 5V output beneficial for industrial sensors?

Industrial sensors like pressure and temperature modules are often designed for 5V input-adjustable regulators require external resistors to set this voltage, adding components and calibration time. The L6981N50DR??s fixed 5V output eliminates this. An engineer noted ??we no longer need trimmers, cutting component count by 20% and calibration errors by 95%. This also saves 10% PCB space, critical for compact sensor nodes.??

How does the wide input range help home appliance designs?

Home appliances use diverse power sources: 12V for small devices (blenders) and 24V for larger ones (refrigerators). The 7V?C25V range handles both without external clamps. A designer shared ??this lets us use the same regulator across 3 product lines, standardizing inventory and cutting logistics costs by 25%. We also eliminated external clamps, saving 15% PCB space and simplifying maintenance.??

Can the L6981N50DR operate in cold industrial environments?

Yes. Its -40??C to +125??C operating range handles cold settings (e.g., -30??C freezers, winter outdoor sensors) while maintaining stable 5V output. The SOIC8??s thermal pad also prevents overheating in warm conditions. A freezer sensor maker confirmed ??our sensors run in -25??C freezers; this regulator keeps power stable, with zero shutdowns in 3 years-unlike our old regulator that failed at -15??C.??

What value does low output noise add for IoT data loggers?

IoT data loggers transmit sensitive data (e.g., temperature trends) – high output noise can corrupt signals, leading to data gaps. The L6981N50DR??s ??30??V noise eliminates this. An IoT engineer noted ??our old regulator??s 150??V noise caused 20% data loss; this model cuts loss to 1%, ensuring clients get complete datasets. We also removed 2 filters, saving 15% PCB space and 10% cost.??

How does low dropout voltage extend battery life?

Batteries discharge over time-older regulators stop working when input drops below 9V (for 5V output), wasting remaining battery capacity. The L6981N50DR??s 0.5V dropout lets it operate until input hits 7.5V. A data logger firm shared ??this extends battery life by 25%, from 4 months to 5 months-critical for remote sites. We now replace batteries 20% less often, cutting maintenance costs by 30%.??