ECS-396x SMD Clock Oscillators ECS ECS-396x SMD Clock Oscillators are 3.3V or 5.0V miniature crystal-controlled oscillators with a 3.2mm x 5mm footprint. The package is seam welded with a metal lid. With a frequency range between 1.000MHz and 125.000MHz, the ECS-396x SMD Clock Oscillators operate in a temperature range of -10°C to +70°C or an extended range of -40°C to +85°C (N option).