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2025-11-25 7:10 pm
Hi everyone,
I’m working on a DIY electronics project that will run from a mains-powered supply and eventually drive some motors and sensitive sensors. To protect the circuit from voltage spikes and surges (especially from motor switching and nearby inductive loads), I’m considering adding a BZ01CA223ZSB TVS diode. According to its datasheet, this part is designed to clamp high-energy transients and absorb surge currents, exactly what I need for protection.
My plan is to place the BZ01CA223ZSB right after the bridge rectifier and the main filter capacitor in the power supply section. That way, any incoming spikes get clamped early before they can damage downstream components like regulators or microcontrollers. I will ensure the diode has a good ground / return path to get the surge safely to ground.
What I’m most interested in testing next: how quickly and reliably the diode clamps during a surge, and whether I notice any leakage or unintended effects under normal operation (some TVS diodes can leak or add capacitance). I also plan to size the copper traces / ground plane carefully to handle the surge currents without burning or creating voltage drops.
So...
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How would you lay it out on the PCB (grounding, trace width, placement) for best surge handling.
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Whether you experienced real surge events and how well the diode protected your circuit.
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Any quirks or unexpected behavior (leakage current, heat, noise) during normal power-up and shutdown cycles.
Thanks in advance. I’m hoping to get a robust, surge-protected design before powering up the motors.
2025-11-28 8:09 pm
I’m hoping to get a robust, surge-protected design before powering up the motors.
Designing a robust circuit of any kind is for the experts and vital for reasons of safety when it comes the surge protected power supplies. It is probably best to buy a surge-protected power supply that fits your specifications in terms of protection rather than try and build one yourself.
2026-02-09 1:59 am
Solid call on the BZ01CA223ZSB—works a treat on my drone builds! Short/wide traces (2-3mm min), straight to main ground. Handles 60A lithium-ion connector peaks, never fried a reg. Only catch: shoddy ground = wonky clamping. Got your motors’ peak surge current yet?
Yassin | Building Compact, High-Current Connections for Drones & Robots
2026-02-10 4:24 pm
Hi @jordanm23,
My 5 second Google suggests the BZ01CA223ZSB is an obsolete supercap ... not a TVS component.
https://www.digikey.at/en/products/detail/kyocera-avx/BZ01CA223ZSB/1014118
Indeed, I would expect a supercap to be liable to fail catastrophically, if it was subjected to an overvoltage.
I wouldn't even consider connecting it to the output of a transformer/bridge rectifier.
2026-03-27 11:58 am
These long part numbers are a bit of a challenge. I wasn't able to access the link in your post.
I'm not an engineer but I do suggest if you want to protect your sensors you have two kinds of protection needs
One is from damage
The other is from interference (in order to get reliable data)
I also suggest you purchase a good power supply so you aren't working with line voltage . The good thing is that they are not all that hard to find used.
You don't say what DC voltage you will be using. I do have a "hack" to offer: Old laptop power bricks.
The power bricks from the top tier laptop manufacturers are of high quality and many of them are rated for 95 watts. Almost all laptop power supplies are for 20 volts regardless of brand. You might even have one kicking around somewhere. So if you can work at 20 volts and need up to 4.5 amps its a low cost solution for getting started.