Diymore 2pcs 20A 300W CC CV Step Down Module Adjustable DC 6-40V to 1.2-36V Voltage Regulator Buck Converter Constant Current Power Supply Module 20v to 12v Step Down

Powers 9 mg90s servos no problem. I fed it with 2p2s 18650s. You do gotta turn the cv and cc screws like crazy till the multimeter catches the voltage. I tried to measure mA but it went to a safe mode, after dc’ the power supply i left it alone and its working fine

Bucked for about 4 minutes, then passed full voltage. Input 40VDC out 24VDC, 4 amps. Tried to adjust & shorted out at rheostat. Garbage. I would advise don't waste your money.

Tried a few low current devices for a light project I've been workin' on. * see Image * They worked but just didn't have enough to expand on. So got some of these 20Amp buck inverters. Been really happy with how much work they can do while maintaining correct potential and current. That said... Each light string is about 1 meter in length. The Inverter doing the most work has 8 strings connected. Supply is 24Volts. At 20 Watts output expect some warmth from the Inverter. Beyond 30 Watts you'll want to put a fan on to cool the Inverter. Something to watch for, inrush is a thing, so if you're using this to run LED strings, be sure to set the potential within specs for the string and then set the current to suit your needs. If you only set the current, there can be an instantaneous in rush which may exceed the LED's limit and reduce their working life. Best luck to you on your project. :)

This works great for taking 4s (or more) lithium ion packs down to 12v. But if your antenna is close, you will likely experience some birdies (picture attached). This was with the antenna beside the device. When I ran the same test with my notmal outside antenna, sove birdies were still visible/audible. So be careful what your intended use is. Otherwise, it works great. I will certainly put this to use with some other projects.

I used these to step down 20V to 12-14V for a kids ride-on car. They work great, but will need manual inspection before use. The modules appear to be hand assembled where the solder work is very poor. Upon visual inspection, I noticed that one of the MOSFETs was accidentally shorted on one module. In the other module, the resistor feeding the indicator LED was not correctly soldered (so the LED didn't work). After manually resoldering the problematic areas, they work fine. For testing, I highly recommend connecting a programmable power supply and setting the output current very low in case there is a short. Despite that quality problems, it's hard to argue with the low price. I would still buy them again as I feel comfortable fixing such problems.

Running these off a 40V 4Ah Ryobi battery to run 2 power wheel motors, and 6 LEDs. MAXED out on the amperage, and at 6V, the car can barely move itself. At 8V, it can move my 30 lb kid, but it's SLOW. I bumped it to 12.1V, and it can move, but my 9 month old crawls faster. I paralleled the second buck converter in, also set to 12.1V, and max amps, and it moves pretty good on hard surfaces (IE concrete/wood floors), but it's kinda slow in the grass. It also is current limiting, as with the drive wheels off the ground, the output from BOTH converters in parallel is only 9V. The battery was at 40V exactly when I checked, and is having no issues supplying the converters.

Works just fine for my use. Gets warm. I couldn’t get it to work. Then I tried adding the relay. Got it to work on a kids huffy torex utv 24v. Dropped voltage from 36v to 24v 👍

Both units lack insulation between the heatsinks and power mosfets, which means that both sides put the input and output voltages onto the sinks. this is not just a step back, but a major safety hazard! I touched one of the sinks and got shocked. Dunno if the lack of isolation here was a manufacturing error or a sadistic ommission/feature but this sucks!!! the boards i was shipped use a TPS40057 buck converter chip, which is different than the other types I’d bought years back. the pcb layout is also different. there are some explicit testing points now. i will update my review in a few days

Soldering quality is very poor. Solderballs everywhere including short circuit on device pins (photo 1). Damage during shipping due to poor packaging with no padding. Broken SMD capacitor as a result (photo 2). Obviously not worth buying.