Is the UNI-T UDP3305S the BEST Programmable Power Supply? Find Out! | Voltlog #478

Are you tired of juggling multiple power supplies on your workbench? The UNI-T UDP3305S could be the solution you’ve been waiting for. This programmable DC power supply unit combines four independent channels into one sleek and powerful package, making your life easier and more productive. With three independently programmable outputs (two at 0-30V 5A and one at 0-6V 3A) and a fixed 5V 2A USB output, the UDP3305S offers a total combined power output of 348W.

Its 1mV/1mA resolution and low ripple voltage of less than 350uV (measured at 1MHz bandwidth) make it suitable for powering even the most sensitive analog circuits. One of the standout features of this unit is its ability to internally switch channels 1 and 2 to series or parallel mode, eliminating the need for external wiring and separate adjustments.

Need more than 30V? Switch to series mode for up to 60V at 5A. Need more current? Parallel mode delivers 30V at 10A. The 4.3-inch TFT display provides a clear and intuitive graphical user interface, allowing you to monitor and adjust settings with ease. The unit also offers advanced features like waveform viewing, programmable sequences, monitoring, triggering, and data logging.

With a robust build quality, rubber corner protection, and a carry handle, the UDP3305S is designed for the demanding workbench environment. Connectivity options include USB, Ethernet, RS232, and digital I/O, enabling remote control and integration into automated test setups. While the included Windows software could be more polished, the instrument itself excels in usability and performance.

Compared to alternatives from Rigol, Siglent, and others, the UNI-T UDP3305S offers more features at a lower cost, making it an attractive choice for professionals and hobbyists alike.

Voltlog #259 – InTheMail

Welcome to a new InTheMail, the series that will touch both your passion for electronics and your bank account at the same time. We’re going to start with this small white box, which looks very uninteresting from the outside but contains something really nice, it’s a machined aluminium heatsink, designed specifically for the raspberry pi 4 and inside the box you get the two halves of the heatsink plus some mounting screws and silicone thermal pads.

There is a decent amount of aluminium in this heatsink, and we can see it has these rectangular raised islands for contact with the main chips on the board, so this is where the silicone pads will go. This is a completely passive heatsink and that’s what I was looking for but if you want more cooling power these are also actively cooled heatsink. feel like I should test this in a separate video to see how efficient it is when compared to a no heatsink solution which we already know doesn’t work well with the raspberry pi as it gets pretty hot. So we’ll leave this for a future video.

Voltlog #246 – What if we install a heatsink on the TPS61088 boost module?

In the previous video where I took a closer look at the TPS61088, I did some measurements of the output noise but I also ran the module up to the maximum specified output power of 12V 2A. It was to be expected that the losses would turn into heat and just the small size of the board would not be enough to dissipate all that heat safely so the boost chip reached a toasty 150 degrees Celsius and inevitably went into thermal protection.

There were two questions that people mainly left in the comments of that video. First people were curious if this module would behave differently if a heatsink was installed and also some people thought about using this module in a fixed configuration, because if you remember there is a chip on this module that will switch the output voltage based on quick charge spec, depending on what the load is requesting through that protocol but people might just want a simple fixed output. To this I would add a third question of my own, what is the real efficiency figure of this module, at the maximum output. 

Voltlog #245 – TPS61088 Boost Module Test (with QC3.0)

The real limitation for this small module to output the claimed 24W for longer periods of time is temperature. There is not enough thermal dissipation happening with this small pcb. Having a bigger pcb with more copper layers would help and it would probably allow this module to output continuously and prevent the TI controller chip from going into thermal overload. Even so I was impressed that running it into thermal protection several times did not do any damage the chip recovered on it’s own each time and no magic smoke escaped during these tests.

So all of this considered, this is probably one of the best dc-dc boost converter modules I got from China so far and I would recommend getting one of these if the specs meet your needs.