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Stable 12V Power for Embedded Builds
The 12V, 4.5A Step-Down Voltage Regulator D42V55F12 is a compact switching regulator for projects that need a lower and more stable DC rail from a higher input source.
It is a strong fit for robots, control boxes, battery-powered builds, and embedded systems that need efficient power conversion with less heat than a linear regulator.
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
- Input voltage: up to 60V (minimum input depends on dropout vs load)
- Output: 12V with 3% accuracy
- Typical efficiency: 85%–95% depending on VIN and load
- Current capability: typical max is 4.5A at 42V in , with a typical continuous range of ~3.5A to 6.5A depending on input voltage and…
- Synchronous buck design for high efficiency and lower heat than linear regulators
- Switching frequency around 400kHz under heavy loads
What you can build
Great for powering 5V or 12V rails in robots, controllers, sensor hubs, SBC projects, vehicle electronics, and custom battery systems.
Compare regulator options
| Model | Topology | Output | Max current |
|---|---|---|---|
| D24V22F12 | Buck | 12 V | 2.2 A |
| D36V28F12 | Buck | 12 V | 2.4 A |
| S13V25F12 | Buck-Boost | 12 V | 2.5 A |
| D42V55F12 | Buck | 12 V | 4.5 A |
| D24V150F12 | Buck | 12 V | 15 A |
| U3V16F12 | Boost | 12 V | — |
| U3V40F12 | Boost | 12 V | — |
Technical specifications
| Product | 12V, 4.5A Step-Down Voltage Regulator D42V55F12 |
|---|---|
| Brand | Pololu |
| Model | D42V55F12 |
| Category | DC-DC Step-Down Regulator |
| Topology | Step-Down (Buck) |
| Output Voltage | 12 V |
| Max Current | 4.5 A |
| 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 × 12V, 4.5A Step-Down Voltage Regulator D42V55F12
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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