ECS-2520S SMD Crystal Oscillators ECS ECS-2520S SMD Crystal Oscillators are miniature (2.5mm x 2.0mm x 0.9mm) surface mount HCMOS tight stability crystal oscillators. The ECS-2520S features a 3.2MHz to 55MHz frequency range and ±15ppm (EN) or ±10ppm (FN) frequency stability within a -40°C to +85°C temperature range. A miniature ceramic package makes these ECS oscillators ideal for wireless and Internet of Things applications, where stability is critical.