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AVDD, DVDD and VREF voltage levels are correct only during reset

Question asked by jayne on Apr 13, 2018
Latest reply on Apr 27, 2018 by Gary.Kang.AnalogDevices


I'm using ADE7878 as an energy meter IC. I powered up my board with 3.3V on VDD pin and tryed to measure AVDD, DVDD and VREF voltage levels. The expected values are 2.5V, 2.5V and 1.2V, respectively, and I got 3.18V, 2.41V and 1.78V. Doing some tests, I realized that while the reset pin is low, these voltage levels are correct. PM0 pin is high and PM1 is low. I am using the crystal LFXTAL012698BULK, which datasheet is attached, with 27pF ceramic capacitors. The crystal is not oscillating. Its parameters are: 1mW max drive level, 15pF load capacitance and ESR of 35 ohms. Am I doing anything wrong? Why do I only get the correct voltages while reset pin is low? And why isn't the crystal oscillating? The part of the schematic containing the ADE connections is also attached to this question.

Thank's in advance.