DX  » Community » Reviews » VMP3203-5V High Efficiency DC-DC Module
View all reviews of this product

2 DXPoints earned for this post

write a review, and get DXPoints

  • Overall Rating: 4
  • Price: 4
  • Quality: 4
  • Ease Of Use: 4
  • Usefulness: 5
Small and powerful – VMP3203-5V High Efficiency DC-DC Module Reviews

posted by Pengi on 06/12/2011 Certified Owner

Involvement:Expert (understands the inner workings) - Ownership:1 week to 1 month

Pros:
- compact
- super efficient
- powerful
- stable, clean power
Cons:
- price (?)
- requires 5V on enable Input
- not really 3A (debatable)
Other:
Bought this just because i was curious if this compact unit could be up to the job of supplying a few 5V devices with sufficient current.
I have a small "cubicle" outside that serves as a garden and i don't have electricity there. But i have a car battery in spare :)
Right now i am using a cigarette lighter plug converter that is rated at 650mA and it barely manages to supply a small MP3 player and usb powered speakers. with this one i added a battery charger, a smartphone (Samsung I9000) and a led rgb lightchain (draws rougly 100mA). all round i was drawing about 1.5A. there was no noticeable heat dissipation and the input current was about 650mA. The calculated efficiency is thus about 90%. When the enable-input is floating or set to ground, the unit draws a barely measurable current which makes it ideal for battery powered systems. I am planning to buy more of these to power hard drives in a server that has no 5V lines, powering and charging mobile devices from my spare car battery which is charged by a solar cell when camping/outside and maybe some equipment on my bicycle, that has a dynamo charged battery too :)
in a test environment i was able to draw about 2.5A. beyond that voltage dropped and began to ripple. i was using a large very low esr capacitorwith 440u.
Bottomline:
Buy this if you need a really small, yet powerful supply. Don't expect the unit to work right away, you need to put a logic level signal (5V) on the EN-Pin to turn it on. this can be easily achieved by a large resistor (10-47k doesn't really matter) and a 5V zener diode. Some may argue about the price but i think it's fair considering i'd probably pay 5 times as much if i bought something similar around here in a shop.
Oh, and don't forget the capacitor on the output. Instead of the suggested 47uF from the datasheet, i'd recommend you not to go any lower than 220uF. What's more important: Use ONLY low or super-low ESR types! "Normal" types will get very hot or even blow up due to the intense ripple current. And if they don't they'd still waste a lot of power impacting your efficiency considerably.

WHY CHOOSE DX.COM?

Get great weekly deals and offers like: Collections