Unlike standard clock oscillators that have a fixed output frequency, the output of VCXOs such as G326 can be tuned 50 to 200ppm up or down from the nominal frequency by varying a control voltage accessed via pad 1 on the device. This control voltage operates on a ‘varactor,’ a voltage variable capacitance tuning diode. Thus VCXOs may be used to dynamically alter the system clock frequency.
Housed in a low mass, ultra-miniature 6-pad SMD package measuring 3.2×2.5×1.0mm, the G326 series VCXOs are available in 1.8, 2.5, 3.3 or 5VDC supply voltage versions and offer CMOS (15pF) or TTL (two gates) output. Additional specifications include rise/fall times of 6ns maximum, duty cycle of 50% ±10% as standard with ±5% available to order, start-up time of 10ms maximum, current consumption of 10 to 45mA dependent on frequency, and linearity of 6% typical, 10% maximum. Ageing is ±3ppm per year maximum.
Available in both commercial (-10 to +70°C) and industrial (-40 to +85°C) operating temperature ranges, the Euroquartz G326 series extends the company’s wide range of VCXOs that are produced with CMOS, PECL, LVDS or sine wave outputs in a wide variety of leaded and surface mount package styles.