hi everybody
I have several EC200A which are not normal. at first PWRKEY voltage is 3.8V but after several minute voltage of PWRKEY goes low (randomly between 0.5V to 1.2V) and unstable so the module goes OFF and MCU cannot power on the module again. after this situation PWRKEY’s voltage periodically goes from 0.5V to 1.2V and this cycle repeat every 3 second. image below is waveform of PWRKEY in AC coupling.
