2359 12V to 5V circuit, remove MP2359 input and power on 12V because there is a 2200uF/16V capacitor, the voltage slowly rises to 12V, this is no problem. Solder the MP2359, input 12V directly and pull it down to about 2.7V, and check it with a multimeter. There is no short circuit. There is no short circuit for the 5V output. What caused this? MP2359 has also been replaced! ! !
Skylar ポストする November 12, 2020
My personal feeling is that your input capacitance is too large. After EN is turned on, your Vin voltage is not 12V, and it takes too long to reach the 12V voltage. At this time, the buck circuit is already working, causing problems with the chip work. The filter capacitor, etc. is not the bigger the better, it should be reasonably configured.
Kennedy ポストする November 12, 2020
1 Does VFB have a voltage of 0.8V?
2 R9 is a bit weird, you can connect a 7805 to EN;
3 C40 can be omitted or put on the output terminal.
Alice ポストする November 12, 2020
The original poster made some trouble 7805 and save trouble.
Eleanor ポストする November 12, 2020
For DCDC circuits, the input capacitance does not need to be that large. In addition, is there a problem with your wiring?
