Smarter, More Compatible, and Uniquely Customizable Power-On Control
At the heart of every ATX power supply lies a crucial but often overlooked component — the ATX timing control circuit. This is what ensures your PC powers on reliably and safely every time you press the button.
Traditionally, power supply designers have relied on standard ASIC chips like the TPS3510 from Texas Instruments to handle this timing logic. While functional, such fixed-function controllers come with limitations — especially when dealing with specialized or non-standard motherboards.
At Pico Box, we took a different path.
Instead of using a fixed ASIC chip, we developed our own ATX timing control algorithm, implemented in a microcontroller (MCU). This approach offers greater flexibility, better compatibility, and opens the door for unique features that aren’t possible with off-the-shelf solutions.
🔄 How ATX Timing Control Works
Here’s a quick recap of the standard ATX power-on sequence:
1. User presses the power button on the PC chassis.
2. The motherboard pulls the PSON# signal low.
3. The power supply detects this active-low signal.
4. After a delay (typically ~300ms), the PSU begins outputting 12V, 5V, and 3.3V rails.
5. Meanwhile, the PSU monitors these output rails — if any over-voltage or fault is detected, it disables the output to protect the system.
This is exactly what the TPS3510 does — and what most generic ATX PSUs follow. But there’s room for improvement.
🧠 Why Pico Box Chose an In-House Microcontroller Algorithm
By replacing the traditional ASIC with our own microcontroller-based timing control, we’ve unlocked several key advantages:
✅ 1. Freedom from a Single Supplier
Relying on one chip from one supplier — like TI’s TPS3510 — puts your product line at risk of supply chain delays, EOL notices, or sudden price changes. With an MCU-based design, Pico Box can source microcontrollers from a variety of vendors, ensuring a more robust and flexible supply chain.
✅ 2. Enhanced Motherboard Compatibility
Not all motherboards behave the same. This is especially true in industrial systems or with no-name OEM motherboards, which may not follow standard ATX signal behavior.
We’ve encountered situations where PSUs using TPS3510 fail to turn on certain boards reliably. Pico Box solved this problem by developing and patenting our own control logic, ensuring smooth startup even for demanding or non-standard platforms.
✅ 3. Custom Features and User Experience
Since we use a programmable MCU, we’re not limited by what an ASIC allows. This opens up exciting possibilities for custom features, such as:
• Soft start tuning for smoother power ramp-up
• LED control effects, like breathing or heartbeat LEDs
• Diagnostics or event logging in future firmware
• Firmware updates or feature expansion down the road
🛡️ Built-In Safety and Protection
Our in-house control logic still includes all the standard protections you’d expect:
• Over-voltage protection (OVP)
• Short circuit detection
• Delayed startup timing (~300ms)
• Safe shutdown if fault is detected
But now, we can fine-tune these behaviors based on specific use cases, environments, or hardware configurations.
⚙️ Designed for the Real World, Not Just the Datasheet
By controlling the timing logic in firmware, we can adapt to real-world edge cases — not just the ideal conditions defined in a datasheet.
Our field-proven algorithm has already helped many customers power up industrial control boards that wouldn’t boot properly with standard PSUs. That’s peace of mind that off-the-shelf timing chips can’t always provide.
💬 Final Thoughts
With more PCs being built for unique environments — from industrial control to off-grid smart homes — your power supply needs to be smarter and more flexible than ever. That’s why Pico Box is proud to lead the way with an in-house ATX timing control algorithm that delivers:
• Better compatibility
• More customization
• Long-term flexibility
• Unique patented solutions for tricky motherboards
Ready to upgrade your build with a power supply that thinks ahead?
👉 Explore Pico Box power supplies — smarter from the inside out.
