The SY87739L is a complete rate independent frequency synthesizer integrated circuit. From a single reference source, this device generates a differential PECL output frequency from 10MHz up to 729MHz. The SY87739L generates an exactly correct reference frequency for common data transport protocols. This is especially important in transponder applications, where a standards compliant protocol data unit must be generated downstream, even in the absence of any signal from the associated upstream interface. In addition, the SY87739L will generate exactly correct reference frequencies for common data transport protocols augmented by forward error correction codes. The SY87739L accepts configuration via a MicroWireTM interface.