Over on ScienceDaily we learn that an international team of scientists have turned a common semiconductor germanium into a superconductor.

Researchers have been able to make the semiconductor germanium superconductive for the first time by incorporating gallium into its crystal lattice through the process of molecular-beam epitaxy (MBE). MBE is the same process which is used in the manufacture of semiconductor devices such as diodes and MOSFETs and it involves carefully growing crystal lattice in layers atop a substrate.

When the germanium is doped with gallium the crystalline structure, though weakened, is preserved. This allows for the structure to become superconducting when its temperature is reduced to 3.5 Kelvin. Read all about it in the team’s paper here (PDF).

It is of course wonderful that our material science capabilities continue to advance, but the breakthrough we’re really looking forward to is room-temperature superconductors, and we’re not there yet. If you’re interested in progress in superconductors you might like to read about Floquet Majorana Fermions which we covered earlier this year.

One part wants 3.3V logic. Another wants 5V. What do you do? Over on the [Playduino] YouTube channel, there’s a recent video running us through a not-so-recent concern: various approaches to level-shifting.

In the video, the specific voltage domains of 3.3 volts and 5 volts are given, but you can apply the same principles to other voltage domains, such as 1.8 volts, 2.5 volts, or nearly any two levels. Various approaches are discussed depending on whether you are interfacing 5 V to 3.3 V or 3.3 V to 5 V.

The first way to convert 5 V into 3.3 V is to use a voltage divider, made from two resistors. This is a balancing act: if the resistors are too small, the circuit wastes power; if they are too large, they inhibit fast signals.

The second approach to converting 5 V into 3.3 V is to use a bare resistor of at least 10K. This is a controversial approach, but it may work in your situation. The trick is to rely on the voltage drop across the series resistor to either drop enough voltage or limit the current flowing through input protection diodes, which will clamp the voltage but also burn out with too much current flow.

The third approach to converting 5 V into 3.3 V is to use chips from the 74AHC series or 74LVC series, such as inverting or non-inverting buffers. These chips can do the level shifting for you.

The easiest approach for going in the other direction is to simply connect them directly and hope you get lucky! Needless to say, this approach is fraught with peril.

The second approach for converting 3.3 V into 5 V is to make your own inverting or non-inverting buffer using, in this case, an N-channel Enhancement-mode MOSFET. Use one MOSFET for an inverting buffer and two MOSFETs for a non-inverting buffer. Just make sure you pick N-MOSFETs with 3.3 V or 5 V gate drive voltage V_GS. Alternatively, you can use a buffer from the 74HCT series.

The video provides a myriad of approaches to level shifting, but you still have to decide. Do you have a favorite approach that wasn’t listed? Have you had good or bad luck with any of the approaches? Let us know in the comments! For more info on level shifting, including things to watch out for, check out When Your Level Shifter Is Too Smart To Function.

Over on YouTube [Drake] from the [styropyro] channel investigates what happens when you take an enormous tungsten incandescent light bulb and pump 30,000 watts through it.

The answer: it burns bright enough to light up the forest at night, and hot enough to cook food and melt metal. And why on Earth would anybody do such a thing? Well [Drake] said it was because he wanted to outdo [Photonicinduction] who had already put 20,000 watts through a light bulb. Nothing like a little friendly competition to drive… progress?

[Drake] says he has purchased the most powerful incandescent light bulb ever made for commercial production. Rated for 24,000 watts (and operated at 30,000 watts) the enormous filament is made from tungsten. The starting current drawn by a light bulb is higher than the operating current, because the resistance of the filament increases with temperature, so it’s prudent to warm the device slowly. To this end [Drake] builds some custom wiring and dials to power the thing. Once that’s done, it’s off to the forest to play!

If you’re interested in over-the-top lighting shenanigans, you might enjoy reading about The World’s Longest Range LED Flashlight.

Here’s a fun rabbit hole to run down if you don’t already have the RP2040/RP2350 PIO feather in your cap: how to serve data without CPU intervention using PIO and DMA on the RP2350.

If you don’t know much about the RP2040 or RP2350 here’s the basic run down: the original Raspberry Pi Pico was released in 2021 with the RP2040 at its heart, with the RP2350 making its debut in 2024 with the Pico 2. Both microcontrollers include a feature known as Programmed I/O (PIO), which lets you configure tiny state machines and other facilities (shift registers, scratch registers, FIFO buffers, etc) to process simple I/O logic, freeing up the CPU to do other tasks.

The bottom line is that you can write very simple programs to do very fast and efficient I/O and these programs can run separately to the other code running on your micro. In the video below, [piers] explains how it works and how he’s used it in his One ROM project.

This is the latest installment from [piers rocks] whose One ROM project we’ve been tracking since July this year when we first heard about it. Since then we’ve been watching this project grow up and we were there when it was only implemented on the STM32F4, when it was renamed to One ROM, and when it got its USB stack. Along the way [piers rocks] was on FLOSS Weekly Episode 850: One ROM To Rule Them All too.

Have you seen PIO being put to good use in other projects? Let us know in the comments, or on the tips line!