Hi! Please excuse me for my English.
A noisy voltage of 4V (they can make noise up to 3.6V) is supplied to the input of LP5907. LDO does a good job of this and we get 3V output with fluctuations of 100mV. However, sometimes, for unknown reasons, there are voltage drops at the output up to 2V with a duration of 500 μs. And sometimes after a voltage drop, it recovers 5 seconds.
An MCU with 10mA consumption is connected as a load. 0603 10μF are connected to the input and output of the LDO (I tried to reduce the output to 4.7 μF and to 1 μF, but without result).
And it is also interesting that by soldering 0603 100nF to the input pins of the LDO, the problem disappears. Tell me, please, how to explain this behavior of the LDO, what is the problem and how to solve it? Thanks!
