PEMENOL 15W DC-DC Buck Boost Voltage Converter, 5V to 3.3V 9V 12V 24V 30V CVCC Step Up/Down Module Adjustable USB Power Supply Module with Shell

Got this usb powered power supply recently, have been very pleasantly surprised by it's versatility and usefulness.I have several usb monitors, y'know those things showing voltage, amps, amphours, watts, temperature, phase of the moon and so on. Thought it would round out my collection, and it has been a great addition.Firstly, it's larger than I expected, about half again the size of the usb monitors I talked about, 3.6"x1.6"x0.7" (90x40x17mm about).It has a very clear and bright back-lit LCD display, shows input voltage and current drawn, output voltage and current drawn, amphours and watts, involves a button push to get some values, but easy to perform.You plug it into a usb supply, be it a power bank, wall-wort, laptop, whatever... and it shows the voltage available. Two brass set-screws on the right side determine the output voltage and current. And it has two springy pushbutton connectors at the right to connect your output leads, AND a usb output socket on the top right, both of which output the set voltage and current. Keep that in mind if you plug stuff into the usb socket on this, as if you have it dialed up to something more than 5v... you may have a bad day involving missing magic smoke. Just be careful!It has an on/off toggle, enabling you to turn on and off the output voltage & current. Also, if you hold the on/off button for several seconds, you can set whether you want the output on by default, or off. I like it off, that way I don't accidently fry something if I've set it to 24v or something previously and hook up new stuff.Another button switches between the input and output voltages & current, and a long press displays amphours and watts.It'll accept inputs from the usual usb jack, and also a type-C socket and a micro-B socket, both flanking the usb jack on the left side. The device will accept 4-13vdc on its inputs, which makes sense since it also has the ability to trigger the higher voltages of QC3.0, QC2.0, and other usb power delivery protocols. The QC and fast charge protocols are controlled via a 'trigger' button, long pressing lets you choose which protocol to use, including off and auto (try them all!!). Neat! And Works Well! I added a short animation of the device detecting and selecting 12v (vs 5v) from my power bank. I thought it was a little odd at first, the display says '9c20' and '9c30'... duh... it's qc2.0 and qc3.0! And then it says 'err' or 'oy' to indicate bad or good protocol selection. Yeah... 'oy'... I *think* it's supposed to be 'OK', but considering the limitations of a 7-segment display, 'oy' is sufficient. Makes me smile when I see it... little guy has an attitude.... when it works, he goes OY! or Oh Yeah!It has a couple LEDS to indicate Fast Charge status (blue is good), output ON/OFF status (green is on!) and Constant Current status (red is CC mode). Easy to understand.I've gotten about 20watts out of it, although it's rated 15W, it has over-temperature protection and over-current, although if you draw too much current with a poor power supply, it'll just brown-out and turn off. No harm done!I like this unit, it's handy and easy to use, quick to hook up (spring clamps!) and has good steady output. I may buy another!As an aside, The manual is decent, can't complain, although I did find a couple parts humorous... The bit about setting the output current limit says to short the output terminals and then adjust the current knob for desired value. Pretty typical method to set output current. But then, several paragraphs down, in the precautions and do's & don'ts section, it says "Do not short output". Uh... guys? That's how you do it! The current limit setting is adjustable on the fly and will display current value as you adjust the knob, so you don't have to short the output....

The media could not be loaded. I bought this to have a simple and portable way to test for voltages on the go. I love that it works as an ammeter and a power supply as well. It’s very simple to use.It has a few functionalities: 1) It’s a Step Down/Up Power Supply, 2) It’s a Voltmeter, 3) It’s an Ammeter, 4) it’s a USB powered thermometer.It’s well made and compact. Buttons are not impressive but are functional and work well enough. It feels nice and robust.Using it was a bit tricky at first, but once you memorize a couple of things it’s easy to use. Pressing and holding the on/off button for 10 seconds switches between two modes: Power Supply (they call it PER) or Multimeter (they call it VAH).As a Power Supply, only the voltage can be set, however it can be turned on or off, and you get to see the current load. In this mode, it provides over current protection, and I tested it by shorting the outputs. It displayed an error, which was impressive for a product like this.As a Multimeter, it’s easy to set up, and is accurate enough for simple projects. I especially liked that it’s really simple to use it to measure current load of projects. One thing to keep in mind is that when using it as a Multimeter, it has to be powered up by a source (through its USB-A male, USB-C female, or Micro USB female ports).

It can adjust the voltage between 0.5V and 30V from a 5V USB-A input. Has constant voltage or constant current mode. It comes not assembled, not sure why maybe due to low demand but fairly easy to put together.

This review applies to the red in color, 4-13V input, 1 to 30V output unit as shown in the photos that should be near this review.I bought this unit to be part of my electronics tool kit as it appeared like it would be a very handy little unit. After using it for several days now, I’m really amazed at what this little power supply can do!The unit arrived on time and was packed well. No instructions were in the box, but the seller provides a link to download a PDF in the item description. Honestly, the unit is so well designed and clearly labeled that I really didn’t need them, except to understand how the TRIG button worked.I really like the design of this unit. Inputs are pretty self-explanatory – there is a standard USB male A input plug, a type C USB input, a micro USB input, and two solder points where one can attach wires. Output is via a USB female A connector or the spring terminals.I like the fact that the designers added those two solder points, as that means you can adapt this power supply to many different input connectors. For example, I could add wires and a Deans-type RC car connector and power the unit from two series Li-Po cells commonly used by RC cars. That’s fantastic.The output spring terminals worked well, firmly gripping the wires I inserted to test the output of the unit. Again with the spring terminals, it’s easy to adapt the unit to whatever you may want to power.The display is clear and backlit, and I found it very easy to read at all different angles. The LED indicators for Constant Current (CC), Constant Voltage (CV), and FC were nice and bright, without being too bright. The adjustment knobs for the CC and CV adjustments are small, but still remain easy to adjust.I did a *lot* of testing on this little supply and it worked great. In fact, one of the pictures shows my test setup – the two purple wires go to my lab power supply, one set of red/black test leads goes to my bench voltmeter, the other set of red/black/white test leads go to my electronic load / ammeter. (in the other two pictures, I did not have the test probes connected, but left the purple wires in place)I found voltage and current accuracy to be within specifications, and as long as my lab power supply could provide enough input current, this unit met the 15 watt out specification…even when the output voltage was very different from the input voltage! For example…when I applied 5 VDC input and set the unit to 13.8 VDC output, it put out 15.2 watts of output! In another test…when I applied 4.5 VDC input and set the unit to 5 VDC output, it easily put out over 2 amps of current. That’s pretty amazing! Output voltage regulation was also very good, sagging at most 0.1 VDC at maximum output current – that’s excellent for the price.The unit is a switching power supply, and as expected, looking at the output on my scope, there is a small amount of noise in the output which is consistent with other switching power supplies I’ve measured. And those other supplies often cost much more than this unit!I verified that the Over Power Protection (OPP) works as specified – shutting off the output if you exceed the maximum output power of the unit. The Over Temperature Protection (OTP) feature also works well, turning of the unit when it gets too hot. Those a very nice design touches, preventing the power supply from being run outside its maximum specifications.Bottom line, this power supply does it all and is an extremely handy addition to my electronics toolkit! With one power supply, I can take a wide range of input voltages - 4 to 13 VDC - and provide a very wide range of output voltages - from 1 to 30 VDC. Simply amazing...especially for under $20!