Just thought this is interesting to share. This is an announcement from HobbyModel.

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We received many reports about the 5v regulator or the mosfet burnt out immediately once the battery plug in

We found that most burnt happened after mod the PH2.0 to XT30 . Also, more powerful the battery is(lower esr than stock battery) , more possibility to fail. And, the temporary solution is add a low esr capacitor onto xt30 connector. This capacitor should have a esr less than 0.2 ohm and have a capacitance more than 100uF. Rubycon ZLG/ZLH series and Samyoung NXB series are what we have tested and recommended.

The attached pictures show what happened after plug in battery

(Picture without capacitor)The max voltage is 19v and the voltage spike lasted for about 5us.
(Picture with 100μF capacitor)After add a 100uF/16v (NXB16VB100M5*11_LO) capacitor, we obtained a much slower and smaller spike



So this capacitor could avoid the risk of burning the mosfet or the 5v regulator at the moment of power on

With this Capacitor , we can use 3S 300~350mah battery for the Crazybee F4 PRO V2.0 and Crazybee F4 PRO V2.1 , and 2s 300~350mah battery for the Crazybee F4 PRO V1.0 And if you want to use the battery above 350mah , we recommend use 220 uF or above capacitor.

The V2 Mobula7 HD and Sailfly-X already use the xt30 pigtail with 100μF capacitor, also the Crazybee F4 pro series flight controller will comes with the capacitor too.

https://www.banggood.com/Happymodel-XT30...76203.html

Thanks for posting this. I'll relay the information on the Trashcan group if someone hasn't already done it.

Bit late for me so I'll continue with my external BEC without a Capacitor to start off with. I have 450mAh 2S LiPos anyway so I would have needed to use quite a large capacitor.

A link to the information on the Happymodel Facebook page is here: https://www.facebook.com/HappymodelCN/po...4854115147