Typically, two VCXOs are needed to switch from an operating frequency to a forward-error-correction rate. Now it can be done in one step with the 7311Q 622.08-MHz series of dual-rate voltage-controlled crystal oscillators (VCXOs) for SONET and SDH applications. They deliver a complementary LVPECL output and include standard FEC frequencies of 644.5133, 666.5143, and 669.3266 MHz. In addition, they produce a low-jitter pure frequency source and operate from 3.3 V dc at 130 mA. Housed in 17.0- by 9.6- by 3.9-mm SMD six-pin L-lead packages, the VCXOs operate from −10 to 70°C with an overall stability of ±50 ppm maximum. In 100-unit lots, they cost $65 each.
NDK America Inc.