STMicroelectronics ST1S10PUR Step-Down DC DC Converter, DFN8 Package for Low-Power IoT

STMicroelectronics ST1S10PUR Step-Down DC DC Converter Overview

The STMicroelectronics ST1S10PUR is a high-efficiency, synchronous step-down (buck) DC DC converter engineered for low-power, space-constrained electronic systems. Optimized for IoT edge devices, portable medical tools, and compact industrial sensors, it integrates a dual low-resistance MOSFET synchronous power stage, programmable output voltage, and ultra-low quiescent current into a tiny package. This design delivers stable, regulated power from a 2.7V?C5.5V input to 0.8V?C3.6V low-voltage loads-making it a top choice for B2B engineers prioritizing energy efficiency, miniaturization, and reliability in battery-powered or space-limited designs.

As a product from STMicroelectronics-a global leader in semiconductor innovation with deep expertise in low-power power management-the converter meets strict quality standards for performance, durability, and environmental compliance (including RoHS 2 certification). Senior engineers at a leading IoT sensor firm endorse it, noting: ??The ST1S10PUR??s 96% efficiency and 1A output let us power 4 sensors in a 12mm x 12mm PCB, with battery life improving by 32% vs. our old 0.6A converter.?? For more trusted industrial ICs and low-power power management solutions, visit IC Manufacturer.

Technical Parameters of ST1S10PUR

Key Technical Features of ST1S10PUR

• Synchronous power stage with low R_DS(on) MOSFETs, eliminating external Schottky diodes and reducing power losses-critical for maximizing battery life in portable devices. A wearable tech designer reported this feature ??cut power loss by 45% vs. asynchronous converters, extending our fitness tracker battery life by 4 days.??
• 1A continuous output current, delivering enough power for multi-sensor arrays (e.g., 4x 0.2A temperature/humidity sensors) without parallel converters. An IoT gateway engineer noted ??one converter powers our entire sensor suite, cutting component count by 70% vs. using two 0.6A regulators.??
• Tiny DFN8 package (2.0mm x 2.0mm) with exposed thermal pad, reducing PCB space by 30% vs. standard SOT23-6 packages and improving heat dissipation by 25%. Industrial automation designers confirm ??this package let us fit the converter in 12mm x 12mm sensor PCBs-something we couldn??t do with bulkier alternatives.??
• Ultra-low 15??A quiescent current (light load) and 0.1??A shutdown current, minimizing standby power waste for battery-powered devices. A wireless environmental monitor firm shared ??standby power use dropped by 85%, letting our devices run for 20 months on one AA battery.??
• Built-in voltage ripple filtering (??20mV peak-to-peak), ensuring stable power for noise-sensitive components like precision medical sensors. A medical tech maker noted ??this feature reduced data errors from power instability by 98%, meeting our clients?? FDA accuracy requirements.??

Advantages of ST1S10PUR Over Alternative Solutions

Compared to lower-current converters (??0.6A), asynchronous converters, or larger-package regulators, the ST1S10PUR delivers three critical benefits for B2B low-power designs-backed by real customer feedback:

First, its 1A output eliminates parallel converter complexity. Lower-current 0.6A models force engineers to use two chips to power 1A loads (e.g., 4x 0.2A sensors), adding cost, PCB space, and failure points. The ST1S10PUR??s 1A output handles these loads with one device. A senior IoT engineer explained: ??We used two 0.6A converters for our 0.8A sensor module; switching to the ST1S10PUR cut PCB space by 45% and component cost by 40%. This also simplified wiring and reduced heat.??

Second, its synchronous design outperforms asynchronous converters in efficiency. Asynchronous converters rely on external diodes that cause significant power losses at high currents, limiting efficiency to 75?C80%. The ST1S10PUR??s integrated synchronous MOSFETs eliminate this loss, boosting efficiency to 96% at typical loads. A portable medical device designer confirmed ??our glucose meter??s battery life jumped from 8 hours to 11 hours with this converter-critical for all-day clinic use. Asynchronous converters couldn??t deliver this runtime.??

Third, its DFN8 package and thermal pad outpace larger alternatives. Standard SOT23-6 converters (3.0mm x 3.0mm) take up 225% more PCB space than the 2.0mm x 2.0mm DFN8, making them impractical for ultra-compact designs. Additionally, the DFN8??s exposed thermal pad prevents overheating at 1A output-an issue that plagues SOT23-6 models. Per STMicroelectronics testing, the DFN8 reduces junction temperature by 20??C at 1A vs. SOT23-6. An industrial sensor firm shared ??our SOT23-6-based design overheated at 0.8A; the ST1S10PUR??s DFN8 package runs 15??C cooler at 1A, eliminating thermal shutdowns and cutting downtime by 8 hours weekly.??

Typical Applications of ST1S10PUR

The ST1S10PUR is engineered to solve low-power, space-constrained power regulation challenges-with proven success in these key B2B use cases:

• Internet of Things (IoT) Edge Devices: Powering 4x 0.2A environmental sensors and 3.3V Wi-Fi modules from 3.7V lithium-ion batteries. IoT solution providers confirm ??devices run for 20 months on one battery, vs. 12 months with old converters, and PCB size shrank by 30%.??
• Medical Devices (Portable): Regulating 3.7V battery power to 1.8V for glucose meter sensors and 3.3V for displays. A medical tech firm noted ??the 1A output handles sensor peak loads, and 96% efficiency extends battery life by 3 hours-critical for patient testing.??
• Industrial Automation (Mini Sensors): Converting 5V industrial power to 0.9V for low-power microcontrollers and 3.3V for data loggers. A factory operator reported ??sensors fit in 12mm x 12mm machinery gaps, and power-related data errors dropped by 96%.??
• Consumer Electronics (Wearables): Step-down 3.7V battery power to 1.2V for smartwatch accelerometers and 3.3V for Bluetooth modules. A consumer tech brand shared ??battery life improved by 32%, and the tiny package let us slim our watch??s design by 20%.??
• Home Appliances (Smart Sensors): Regulating 5V USB power to 3.3V for smart thermostat sensors and 1.8V for motion detectors. A home tech maker confirmed ??sensors use 45% less power, and the small size let us hide them in thermostat housings.??

Frequently Asked Questions (FAQ)

Why is 1A output current important for IoT edge devices?

IoT edge devices often power 3?C4 low-power sensors (0.2A?C0.3A each) plus a microcontroller, totaling 0.8A?C1.0A. Lower-current 0.6A converters require parallel chips, adding cost and space. The ST1S10PUR??s 1A output handles these loads with one device. An IoT engineer noted ??this cut our sensor module PCB space by 45% and component cost by 40%, while also reducing heat from parallel regulators-making our devices smaller and more reliable.??

How does ultra-low quiescent current extend battery life?

Many battery-powered devices (e.g., wireless sensors) spend 99% of their time in standby (sampling data once per minute), so quiescent current (idle power) dominates battery life. The ST1S10PUR??s 15??A quiescent current is 70% lower than 50??A alternatives, drastically reducing standby waste. A environmental monitor designer shared ??our devices used 50??A in standby before; 15??A cuts that by 70%, extending battery life from 12 months to 20 months-reducing customer maintenance costs significantly.??

Can the ST1S10PUR handle voltage fluctuations from lithium-ion batteries?

Yes. Its 2.7V?C5.5V input range easily handles lithium-ion battery discharge cycles-e.g., 3.7V cells that drop from 4.2V (full charge) to 2.7V (empty). The converter maintains stable 0.8V?C3.6V output even as input varies, preventing load damage. An IoT sensor maker confirmed ??our 3.7V battery-powered sensor stayed operational until the battery hit 2.7V, vs. shutting down at 3.0V with our old converter-adding 3 weeks of runtime. This is a huge win for our clients.??

What value does the exposed thermal pad add for low-power designs?

Even low-power devices (1A output) generate heat that can cause thermal shutdown in converters without proper dissipation. The ST1S10PUR??s DFN8 package has an exposed thermal pad that transfers heat directly to the PCB, improving dissipation by 25% vs. padless packages. An industrial automation engineer noted ??our 1A load caused a padless converter to shut down weekly; this one runs 20??C cooler, with zero thermal issues in 3 years. It??s eliminated costly factory downtime from overheating.??

How does voltage ripple filtering benefit medical devices?

Medical devices (e.g., glucose meters, pulse oximeters) use precision sensors sensitive to voltage ripple-even 30mV ripples can cause 10?C15% data errors. The ST1S10PUR??s built-in filtering limits ripple to ??20mV peak-to-peak, ensuring stable power. A medical tech firm shared ??our glucose meters had 8% error with a non-filtered converter; this one cuts error to 0.5%, meeting FDA accuracy standards. We no longer need external capacitors, saving space and cost in our portable designs.??