Collaborate Disseminate
[Hesam Moshiri] has built a variable switch-mode power supply over on hackaday.io. When prototyping a new circuit, often the goal is to get a proof-of-concept working as soon as possible to iron out all of the bugs it might have. The power supply can easily be an afterthought, and for …read more
When designing a mains power supply for a small load DC circuit, there are plenty of considerations. Small size, efficiency, and cost of materials all spring to mind. Potential lethality seems like it would be a bad thing to design in, but that didn’t stop [Great Scott!] from exploring capacitive …read more
Continue reading Mains Power Supply for ATtiny Project is Probably a Bad Idea
“They don’t build ’em like they used to.” There’s plenty of truth to that old saw, especially when a switch-mode power supply from the 1940s still works with its original parts. But when said power supply is about the size of a smallish toddler and twice as heavy, building them like the old days isn’t everything it’s cracked up to be.
The power supply that [Ken Shirriff] dives into comes from an ongoing restoration of a vintage teletype we covered recently. In that post we noted the “mysterious blue glow” of the tubes in the power supply, which [Ken] decided …read more
In the last installment of Circuit VR, we walked around a simplified buck converter. The main simplification was using a constant PWM signal. The result is that the output voltage is a fixed fraction of the input voltage. For a regulator, the pulse width will need to depend on the output voltage so that any changes in the output are self-correcting. So this time, we’ll make a regulator, although we’ll still use a few Spice elements you’d have to replace in a practical design. In particular, we’ll assume you can generate a triangle wave, which is easy enough, and produce …read more
Continue reading Circuit VR: An (Almost) Practical Buck Converter
The first thing I ever built without a kit was a 5 V regulated power supply using the old LM390K. That’s a classic linear regulator like a 7805. While they are simple, they waste a lot of energy as heat, especially if the input voltage goes higher. While there are still applications where linear regulators make sense, they are increasingly being replaced by switching power supplies that are much more efficient. How do switchers work? Well, you buy a switching power supply IC, add an inductor and you are done. Class dismissed. Oh wait… while that might be the best …read more
We always appreciate when someone takes the time to build something and then demonstrates what different design choices impact using the real hardware. Sure, you can work out the math and do simulations, but there’s something about having real hardware that makes it tangible. [Julian Ilett] recently posted two videos that fit this description. He built a buck converter and made measurements about its efficiency using different configurations.
The test setup is simple. He monitors the drive PWM with a scope and has power meters on the input and output. That makes it easy to measure the efficiency since it …read more
Everyone needs a bench power supply, and rolling your own has almost become a rite of passage for hackers. For a long time, the platform of choice for such builds seemed to be the ATX power supply from a computer. While we certainly still see those builds, a lot of the action has switched to those cheap eBay programmable DC-DC converters, with their particolored digital displays.
This hybrid bench and portable power supply is a good example of what can be accomplished with these modules, and looks like it might turn out to be a handy tool. [Luke] centered his …read more
Continue reading Hybrid Bench Power Supply Can Also Hit the Road
We’re suckers for miniaturization projects. Stuff anything into a small enough package and you’ve probably got our attention. Make that something both tiny and useful, like this 5-volt to 3.3-volt converter in a TO-220 sized package, and that’s something to get excited about. It’s a switch mode power supply that takes the same space as a traditional linear regulator.
Granted, the heavy lifting in [Kevin Hubbard]’s diminutive buck converter is done by a PAM2305 DC-DC step-down converter chip which needs only a few supporting components. But the engineering [Kevin] put into this to squeeze everything onto a scrap of PCB …read more
Continue reading A DIY 5V-3V Switching Converter in the Space of a TO-220 Package
Love them or hate them, Nixies are here to stay. Their enduring appeal is due in no small part to the fact that they’re hardly plug-and-play; generating the high-voltage needed to drive the retro displays is part of their charm. But most Nixie power supplies seem to want 9 volts or more on the input side, which can make integrating them into the typical USB-powered microcontroller project difficult.
Fixing that problem is the idea behind [Mark Smith]’s 5-volt Nixie power supply. The overall goal is simple: 5 volts in, 170 volts out at 20 mA. But [Mark] paid special care …read more
Continue reading Nicely Engineered Boost Converter Powers Nixies from USB Charger