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Raise Low Input Voltage with 5V Step-Up Voltage Regulator U3V40F5
The 5V Step-Up Voltage Regulator U3V40F5 boosts a lower DC input up to a regulated output, making it useful when your source voltage falls below the level your load needs.
It works well in battery builds, portable electronics, and small robots where input voltage can sag over time.
Important: Choose a regulator based on your full input-voltage range, startup current, thermal limits, and required headroom. Real output current depends on input voltage, airflow, and temperature.
Why you'll love it
- Typical efficiency: ~90–95% (VIN/load dependent)
- Switching frequency: ~600kHz under heavy loads + power-save mode (keeps operation above 20kHz)
- No-load current: typically under 2mA; EN low-power state typically ~35µA per volt on VIN
- Current behavior: up to 9.5A instantaneous input, ~4.5A for several seconds, ~4A for prolonged durations (thermal dependent)
- Boosts low-voltage sources (down to 1.3V after startup) to a stable 5V
- Great for battery projects where 5V is required (MCUs, sensors, radios, small SBC accessories, etc.)
What you can build
Useful for battery projects, portable devices, LED systems, and electronics that need a higher rail from a lower source voltage.
Compare regulator options
| Model | Topology | Output | Max current |
|---|---|---|---|
| U3V40F5 | Boost | 5 V | — |
| S13V10F5 | Buck-Boost | 5 V | 1 A |
| D24V10F5 | Buck | 5 V | 1 A |
| S13V20F5 | Buck-Boost | 5 V | 2 A |
| D24V22F5 | Buck | 5 V | 2.5 A |
| D36V28F5 | Buck | 5 V | 3.2 A |
| D30V30F5 | Buck | 5 V | 3.4 A |
Technical specifications
| Product | 5V Step-Up Voltage Regulator U3V40F5 |
|---|---|
| Brand | Pololu |
| Model | U3V40F5 |
| Category | DC-DC Step-Up Regulator |
| Topology | Step-Up (Boost) |
| Output Voltage | 5 V |
| Support | Official Pololu product search and support resources linked below |
Official resources
Find this product on Pololu | Pololu support and resources
What’s in the box
1 × 5V Step-Up Voltage Regulator U3V40F5
Frequently Asked Questions
Can I power a microcontroller with this?
Yes, if the regulator’s output voltage and current match your controller and all attached loads.
Yes, if the regulator’s output voltage and current match your controller and all attached loads.
Will it run cool at full load?
It depends on input voltage, airflow, and load current. Check thermal limits in the official Pololu resources.
It depends on input voltage, airflow, and load current. Check thermal limits in the official Pololu resources.
Is this better than a linear regulator?
For many builds, yes. Switching regulators are usually more efficient and waste less heat.
For many builds, yes. Switching regulators are usually more efficient and waste less heat.
Manila stock. Order before 16:00 PHT, ships today via J&T or LBC. Provincial: 1–3 working days.
Schools / class POs: we accept Purchase Orders for accredited schools and universities. contact us with your PO details.
Returns: 7-day inspection window for DOA units. Email proof of issue and we ship a replacement.
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