Hobbywing 3A U-BEC UBEC (30pcs)
Output: 5V/3A and 6V/3A switchable
Input: 5.5V-26V (2-6 cells Lipo battery pack or 5-18 cells NiMH battery pack)
Size: 41.6mm*16.6mm*7mm (L*W*H)
The UBEC is an advanced switching regulator with over-current and over-heat protection function,and the maximun efficiency of the system is nearly 90%.
The small size and the light weight make it very convenient to use.
The comparison of linear BEC and switch-mode BEC:When using a lithium battery pack more than 3S,a switch-mode BEC has much higher efficiency than linear BEC.
For a traditional linear BEC,For example,a 4S lithium battery back has a typical voltage of 14.8V,in order to let BEC output 5V/1A,the current flow into the BEC is at least 1A,so the power on BEC is 14.8V*1A=14.8W.But the useful output power is only 5V*1A=5W,so the efficiency of the linear mode BEC is just 5W/14.8W=33.8%,the redundant power 14.8W-5W=9.8W changes to heat,which makes the BEC very hot.
For a switch-mode BEC in the above case,in order to let BEC output 5V/1A, the current flow into BEC is only 0.38A(actual test data),so the power on BEC is 14.8*0.38A=5.6W,and the efficiency of BEC is 5W/5.6W=89.3%.
Do not worry about the polarity of battery pack.If the polarity is not correct,the UBEC can not work,but it will not be destroyed.What you need to do is just swap the battery pack polarity.
A shield covers almost all the electronic components on PCB,and a perrite ring is attached with the output wires to decrease the electromagnetic interference.