Integer-N Synthesizer Integrates VCO

The first device in a family of integer-N frequency synthesizers with integrated VCO, the LTC6946 specifies a -226 dBc/Hz normalized closed-loop in-band phase noise, -274 dBc/Hz normalized in-band 1/f noise, and a -103 dBc spurious output. In a 900-MHz application, these specs help to achieve a closed-loop phase noise of -100 dBc/Hz at 1 kHz offset. The device is available in three frequency options: the LTC6946-1 tunes from 2.240GHz to 3.740GHz; the LTC6946-2 from 3.080GHz to 4.910GHz; and the LTC6946-3 covers 3.840GHz to 5.790GHz. In addition, each part has an on-chip output divider that is programmable from 1 through 6 to extend frequency coverage to as low as 373 MHz. All versions of the LTC6946 are specified over the full case temperature range from -40°C to +105°C. Available in 4 mm x 5 mm, 28-lead plastic QFN packages, prices start at $5.75 each/1,000. LINEAR TECHNOLOGY CORP., Milpitas, CA. (800) 454-6327.